Entry Level Certificate
Specification 5948
Science
Support Material
25/06/2012 10:27:46
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Entry Level Certificate
Specification 5948
Science
Support Material
Version 1.0 - 010812
Support Book – ELC Science 5948
1
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CONTENTS
Page number
Introduction
3
Layout
4
Subject Content Index
Biology
Component 1:Keeping Healthy
Component 2:Inheritance, Evolution
and the Environment
2
5
15
Chemistry
Component 3:Materials from the Earth
Component 4:Oils, Earth and Atmosphere
26
38
Physics
Component 5: Energy Transfer and Efficiency
Component 6:Electricity and Waves
52
65
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INTRODUCTION
Purpose
This booklet has been produced to aid ELC teachers who are not necessarily specialists in
science. It should be read in conjunction with the specification.
It is recognised that many teachers who deliver the content of this specification may well be special
educational needs (SEN) teachers rather than science teachers. The aim is therefore to provide
some further background information and where possible to set the topics in their correct contexts.
Please be aware, however, that any extra words, ideas, concepts or facts contained in this booklet
that are not contained within the published ELC specification will not be required by the students
for the examination.
This booklet therefore attempts to illustrate the specification content, but does not amplify or
expand the specification content.
It is not the intention that this booklet should provide teaching strategies. There are examples of
schemes of work and worksheets on the AQA website.
How to use this booklet
Although this booklet has been produced primarily to support teachers, some teachers may wish to
photocopy some of the pages in order to give to their students as resource material.
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Entry Level Support Material
The layout is as follows:
Outcome:

Each outcome, as printed in the specification, is reproduced here.
Key Facts:
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
In order to provide teachers with a little more background to the subject, extra
information is included here.
These facts are not always required by the candidates.
Key Words:
This section contains all the specialist scientific terms contained in the component, with
definitions attached to them for the purpose of assessment. “Key words” will be the only
scientific words of which candidates will need to know the meaning. Other scientific words are
used in the specification, but candidates will not be required to provide a definition of those for
the assessments.
What has been provided is an interpretation of words and concepts for the purpose of the Entry
Level examination, as scientific terminology is still required at this level. The aim has therefore
been to provide a minimum acceptable definition in terms of scientific accuracy, although
obviously a candidate providing a better definition in an assessment would be credited. In
accordance with this aim, there will be occasions on which the definition provided is, of
necessity, a very restricted one, perhaps not applicable in all situations.
Note that the order in which key words appear in the booklet might not necessarily be the same
as the order in which candidates will encounter them or learn them. However, an index of key
words has been provided so that it is easy to cross-reference from one section to another.
Notes:
4
These appear at the end of each page and may include diagrams, charts, graphs,
maps or other types of illustrative material. Sometimes there are no additional
notes.
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Component 1: Biology
Keeping Healthy: diet, exercise, drugs, diseases
and hormones
Outcome 1:
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Reflex actions are automatic and rapid.
Examples include the response of the pupil in the eyes to bright light, and the knee jerk
reaction.
Knowledge of the reflex arc is not required.
Key Facts:
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A reflex action is one that happens automatically, and usually very quickly.
We have no control over reflex actions.
The brain is not involved in reflex actions.
Key Words:
Action
-
Automatic
-
Pupil
Reflex action
-
any movement which our body carries out, such as kicking, walking or
blinking.
means that it happens without thinking about it. We cannot control
automatic reactions.
a circular ‘hole’ in the coloured part of the eye through which light enters.
a reflex is an automatic response of the body. It usually happens very
quickly, and it often helps to protect our body. We do not have to think
about reflex actions.
Notes:
A good example is blinking when something is about to go in your eye.
Another example is the pupil in the eye contracting suddenly when a bright light is switched on.
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Outcome 2:
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A healthy diet contains the right balance of the different foods you need and the right
amount of energy.
Knowledge of different food types is limited to carbohydrates, fats and proteins and
examples of sources of each.
Knowledge of the effects of an unbalanced diet is limited to a person being overweight
or underweight.
No knowledge of deficiency diseases is required.
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Key Facts:
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Carbohydrates, eg sugars, give us ‘instant energy’.
Fats also give us energy, but can act as an energy store.
Proteins are needed to build and repair cells.

Key Words:
Balanced diet
Carbohydrate
Diet
Fat
Protein
- a balanced diet is one that contains the correct proportions of
carbohydrates, fats and proteins. If too much or too little of one of these
is present, the diet will be unbalanced.
- one of the three main food groups. Carbohydrates can give lots of
energy and include starches and sugars.
- the total food consumed by an animal or human.
- one of the three main food groups. Fats are greasy like oils. They can
give more energy per gram than carbohydrates.
- one of the three main food groups. Proteins are needed by the body for
growth and repair.
Notes:
The table shows some common sources of carbohydrates, fats and proteins.
Food type
6
Common sources
Carbohydrates
Cake, sweets, bread, potatoes, cereals, noodles, fruits and vegetables.
Fats
Butter, margarine and oil are obvious sources of fat. Milk, cheese, ice
cream, nuts, seeds, salad dressings and some baked products also
contain lots of fat.
Proteins
Fish & seafood, poultry, milk, cheese, yogurt, eggs, beans, soya, red meat
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Outcome 3:
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People who exercise regularly are usually fitter than people who take little exercise.
The concept of fitness is limited to the rate at which the pulse rate returns to normal for
a person after exercise.
Key Facts:
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People who exercise regularly are usually fitter than people who take little exercise.
Normal pulse rate varies greatly from one person to another.
The most important factor is not what your normal pulse rate is, but how quickly it
returns to what is normal for you, after you have exercised.
The faster your pulse rate returns to normal after exercise, the fitter you are.
Key Words:
Fitness
Pulse
Pulse rate
- a general state of good health, usually as a result of exercise and
nutrition.
- a throbbing that can be felt in an artery. It is caused by the heart pumping
blood through the artery.
- the number of pulses that can be felt in a certain time. A typical resting
pulse rate would be 80 beats per minute.
Notes:
Fitness is very difficult to define. What is ‘being fit’ for a teenager will not be the same as
for a person in their nineties.
Candidates should be familiar with how to measure a pulse rate, eg by detecting the pulse
in the wrist.
They should also be familiar with graphs of pulse rate.
Who is the fitter John or David?
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Outcome 4:
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Drugs affect our body chemistry.
Drugs change the chemical processes in people’s bodies so that they may become
dependent or addicted to them and suffer withdrawal symptoms without them.
Medical drugs are developed and tested before being used to relieve illness or disease.
Some people use drugs recreationally. Some of these drugs are legal, some illegal.
Knowledge of specific drugs is limited to the fact that cannabis is an illegal drug.
Key Facts:
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Drugs are often used properly to cure an illness. Drugs can also be misused if they are
taken for the wrong reasons.
Heroin and cocaine are substances that are often misused and can cause harm to the
body.
It is illegal to possess heroin and cocaine unless they are prescribed to you by a doctor.
Cocaine is an addictive drug that makes users feel super-alert, but get depressed
afterwards.
Heroin is an addictive drug that makes users feel relaxed and warm.
Key Words:
Addictive
-
Cannabis
-
Drug
-
an addictive substance is one that your body becomes dependent on:
once you start taking it, you want more and it is difficult to give up.
an addictive drug, also known as marijuana.
a substance not normally found in the body that is taken to bring about a
particular effect.
Notes:
All drugs are potentially dangerous. Some drugs can be very useful if used properly and for the
correct purpose – but always read the instructions. The misuse of any drug can be very
dangerous.
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Outcome 5:
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Bacteria and viruses may reproduce rapidly inside the body and may produce poisons
(toxins) which make us feel ill.
Viruses damage cells in which they reproduce.
No recall of specific illnesses is required.
Key Facts:
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Bacteria and viruses are tiny microscopic organisms.
They can both grow rapidly inside our bodies.
Some bacteria are useful to us, but other can make us ill.
It is not the bacteria themselves that cause the harm; it is the poisons that they produce
as a waste product that cause the illness.
Key Words:
Bacteria
-
Toxin
Virus
-
are tiny microscopic single-celled organisms. Some are good for the body;
others can cause illness and disease.
a type of poison.
these are even smaller than bacteria. They can live inside body cells and
cause illness and disease.
Notes:
Candidates will not be required to recall the names of specific illnesses or know which are
caused by bacteria and which are caused by viruses.
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Outcome 6:
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White blood cells help to defend against bacteria by ingesting them.
Red blood cells are responsible for transporting oxygen around the body.
Knowledge of the production of antibodies is not required.
Key Facts:
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Some of the cells in the blood help us to remain healthy.
There are several different types of cell in the blood. Some are called ‘white blood cells’,
others are called ‘red blood cells’.
The white blood cells can ‘eat’ bacteria and so get rid of them from our blood.
White blood cells are part of the body’s natural defence mechanism.
Key Words:
Ingest
Red blood cell
-
White blood cell -
this is a scientific word for ‘eat.’
a type of cell found in the blood. It is used to carry oxygen around the
body.
one of the different types of cell found in the blood. They help us to fight
diseases.
Notes:
White blood cells can also help to fight illness by producing antibodies, but candidates are not
required to know this. The only function of white blood cells that they are required to know is that
they can ingest bacteria.
The diagram shows a white blood cell about to “eat” a germ.
Bacteria
Red blood cells are shaped like a doughnut and have no nucleus.
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Outcome 7:
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Antibiotics, including penicillin, are medicines that help to cure bacterial disease by killing
infective bacteria inside the body, but cannot be used to kill viruses.
The names of any antibiotics other than penicillin are not required.
Key Facts:


Antibiotics can be used to treat certain diseases.
They are effective against bacteria, but not viruses.
Key Words:
Antibiotic
-
Penicillin
-
a substance that reduces or stops the growth of microorganisms, such as
bacteria.
a type of antibiotic. It was one of the first ones to be produced.
Notes:
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Outcome 8:
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Many processes within the body are coordinated by chemical substances called
hormones.
Hormones are secreted by glands and are transported to their target organs by the
bloodstream.
No knowledge of the names of specific hormones is required.
Key Facts:
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
Hormones are chemical substances that act as ‘messengers’ around the body.
They are released in one part of the body and travel round to another part, where they have
an effect.
The part of the body that produces the hormones is called a gland.
The part of the body that receives the hormone is called the target organ.
Key Words:
Bloodstream
Coordinated
-
Glands
Hormones
-
Secreted
Target organ
-
is the flow of blood through the various blood vessels in the body.
if processes are coordinated it means that they are working together for
the same purpose.
organs in the body that make hormones.
chemical messengers that carries a signal from one cell (or group of
cells) to another via the blood.
when hormones are released into the blood they are said to be secreted.
this is an organ in the body which receives the hormone and produces a
response.
Notes:
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Outcome 9:
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
Several hormones are involved in the menstrual cycle of a woman, including some that
are
involved in promoting the release of an egg.
Notes:
No further details of the menstrual cycle are required.
Key Facts:
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An egg has to be released from the ovary before it can become fertilised.
The release of eggs is controlled by hormones in the woman’s body.
The menstrual cycle lasts about 28 days.
An egg is released around day 14.
At the end of the cycle, the lining of the womb is replaced. This is known as menstruation,
or a period.
Key Words:
Egg
Menstrual cycle
- the female reproductive cell. When fertilized it can develop into an
embryo.
- this is a recurring series of changes that occur in a woman’s body.
These changes are brought about by hormones, and are linked to
reproduction.
Notes:
Candidates may benefit from seeing a simple diagram of the menstrual cycle, such as the one
below.
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Outcome 10:
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The uses of hormones in controlling fertility include:
- giving oral contraceptives which contain hormones that inhibit eggs from maturing
- giving ‘fertility drugs’ to stimulate eggs to mature.
No knowledge of the names of the hormones involved, or the mechanism by which they
work, is required.
Candidates may be required to evaluate the benefits of, and the problems that may
arise from, the use of hormones to control fertility.
Key Facts:
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Not all women have the same ability to produce babies; that is their fertility may be different.
Fertility is affected by the presence of certain hormones in the blood.
Some hormones can increase fertility, whereas other hormones can reduce fertility.
Fertility may be increased by the woman being given certain hormone treatments.
Fertility treatment can have undesirable side effects as well as having benefits.
One of the undesirable side effects of fertility treatment is that it may result in multiple
births.
Fertility may be reduced by the woman taking oral contraceptives containing another type of
hormone.
Key Words:
Fertility
Inhibit
Oral
Contraceptive
Mature
Stimulate
- this is the natural ability to produce another living being. If a woman is
fertile it means that she has the ability to produce a baby.
- means to prevent.
- means taken into the body through the mouth.
- a method designed to prevent the fertilisation of an egg.
- to grow to full size.
- to provide a signal that will produce a response. Eggs will not grow to
maturity until they receive a signal to do so.
Notes:
If asked to evaluate the effects of fertility treatment, candidates should be aware of both
the advantages and the disadvantages.
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Component 2: Biology
Inheritance, Evolution and the Environment
Outcome 1:
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
Plants often compete with each other for light and space and for water and nutrients from
the soil.
Candidates will not be required to recall any specific examples.
Key Facts:
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

Light and water are both needed for plants to grow.
Supplies of light and water may be limited in certain areas.
Some plants may grow very tall in order to reach light which has been shaded out by
others.
Some plants may grow very long roots in order to try to find water in the soil.
Key Words:
Compete
-
Nutrients
-
to try to win or take away from others. Some plants take available light
and water supplies away from others.
chemical elements that are essential for growth. Plants absorb their
nutrients through their roots. The nutrients are dissolved in water in the
soil.
Notes:
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Outcome 2:
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Animals often compete with each other for food, mates and territory.
Candidates will not be required to recall any specific examples.
Key Facts:
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
In order to survive, animals need food to eat, a member of the opposite sex for
reproduction, and enough space in which to live.
All of these things may be in short supply, and so animals may fight each other for available
resources.
Key Words:
Mates
-
Territory
-
in order to make sure that the species survives, animals need to find a
partner in order to reproduce.
this is the area in which the animal lives, and contains the food and
shelter that it needs.
Notes:
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Outcome 3:
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Animals and plants may be adapted for survival in the conditions where they normally live.
Examples may include polar bears in the Arctic, or cacti in deserts.
Key Facts:
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
The places where plants and animals live can be very different, eg in temperature, water
supply or availability of food.
In deserts, it is very hot, with very little water. In plants like cacti, the leaves have become
spines. This reduces the surface area through which water could be lost.
Key Words:
Adapted
-
Survival
-
over millions of years, plants and animals change or evolve. For
example, polar bears that have thicker fur may be better able to survive.
These animals will then reproduce others which have thicker fur. Over
many thousands of years, the average thickness of the polar bear’s fur
will become thicker. We say that the animal has adapted to suit the
conditions where it lives.
this is the ability to stay alive.
Notes:
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Outcome 4:
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Animals and plants are subjected to environmental changes.
Such changes may be caused by living or non-living factors.
An example of a living factor is a change in a competitor.
An example of a non-living factor is a change in the average temperature or rainfall.
Key Facts:
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Over a long period of time, conditions may change in the area where a plant or animal lives.
For example, it may become much hotter or colder, or water may become in short supply.
If the change in conditions is extreme, and lasts for a long period of time, some species
may not be able to survive.
If the species dies out completely, it is said to be extinct.
Extinction may be caused by changes to the environment, eg changes to climate or food
supplies.
Key Words:
Extinct
-
Environment
-
this means that the species has died out and no individuals of that
species are alive today.
your environment is the place where you live and all the things that affect
it. Things that affect it may include the weather, the activities of other
people, animals or plants, and the availability of food and shelter.
Notes:
It is sometimes convenient to distinguish between the local environment and the global
environment, but knowledge of these terms will not be required.
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Outcome 5:
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Radiation from the Sun is the source of energy for living organisms.
Green plants and algae absorb a small amount of the light that reaches them.
The transfer from light energy to chemical energy occurs during photosynthesis.
This energy is stored in the substances that make up the cells of the plants.
Candidates should know the word equation for photosynthesis.
Carbon dioxide + water → sugar + oxygen
Key Facts:
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Carbon dioxide is removed from the environment by green plants and algae for
photosynthesis.
The carbon from the carbon dioxide is used to make carbohydrates, fats and proteins,
which make up the body of plants and algae.
When green plants, algae and animals respire, some of this carbon becomes carbon
dioxide and is released into the atmosphere.
Key Words:
Algae
-
Carbon dioxide
Cell
Chlorophyll
Organism
Radiation
-
Photosynthesis -
single celled or multiple celled organisms formerly classified as plants.
They are found in fresh or salt water or moist ground. They have
chlorophyll and other pigments but lack true stems, roots, and leaves.
an invisible gas which is produced by burning fuels and by respiration.
the smallest unit or ‘building block’ of an animal or plant.
the green pigment in plants which is necessary for photosynthesis.
a living animal or plant.
this is the process by which heat and light reaches the Earth from the
Sun.
the process of using light energy from the Sun to make chemical energy
in the form of substances such as sugars.
Notes:
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Outcome 6:
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Living things remove materials from the environment for growth and other processes.
These materials are returned to the environment either in waste materials or when living
things die and decay.
Materials decay because they are broken down (digested) by microorganisms.
Microorganisms are more active and digest materials faster in warm, moist, aerobic
conditions.
Key Facts:
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
Carbon dioxide is removed from the environment by green plants and algae for
photosynthesis.
The decay process releases substances that plants need to grow.
In a stable community, the processes that remove materials are balanced by processes that
return materials. The materials are constantly cycled.
Key Words:
Aerobic
Microorganism
–
means in the presence of oxygen.
this is an organism that is too small to be seen with the naked eye, but
can be seen under a microscope. Microorganisms include bacteria,
viruses and some fungi. Many of these microorganisms are very useful to
us because they break down waste products.
Notes:
It is sometimes convenient to distinguish between the local environment and the
global environment, but knowledge of these terms will not be required.
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Outcome 7:
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The nucleus of a cell contains chromosomes.
Chromosomes carry genes that control the characteristics of the body.
Candidates should know that a cell consists of a nucleus that controls the actions of the
cell, and cytoplasm.
Key Facts:
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Genes carry the information for making new individuals.
Some characteristics are controlled by more than one gene.
Most genes have more than one form. For example, the gene for colour in pea seeds may
produce green seeds or yellow seeds.
Different genes control the development of different characteristics.
Key Words:
Characteristics
-
Chromosomes
-
Cytoplasm
Genes
-
Nucleus
-
these are features that distinguish one person from another, eg shape of
nose or colour of eyes.
thread-like structures found in the nucleus of a cell. They carry the
genes.
a gel-like substance that fills the cell.
these are found inside living cells. They carry the information for making
new individuals.
a structure within a living cell, containing the cell's hereditary material and
controlling its metabolism, growth, and reproduction.
Notes:
No knowledge of DNA is required.
A simple cell
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Outcome 8:
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The information that results in plants and animals having similar characteristics to their
parents is carried by genes, which are passed on in the sex cells from which the offspring
develop.
The term gametes is not required.
Sexual reproduction involves the joining of male and female sex cells.
The mixture of genetic information from two parents leading to variety in the offspring.
Key Facts:
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In animals, the genes are passed on to the offspring through the male sperm and the
female egg.
In plants, the genes are passed on through the male pollen and the female ovule (egg).
In sexual reproduction, the offspring will receive genes from both parents.
Because they have a different mixture of genes, offspring born to the same parents will be
slightly different from each other.
Key Words:
Characteristics
-
these are features that distinguish one person from another, eg shape of
nose or colour of eyes.
Genes these are found inside living cells. They carry the information for making
new individuals.
Sexual reproduction - this is a process by which a new individual animal or plant can be
made. It involves two parents, one male and one female.
Variety
- individual animals and plants that are not identical to each other, but
which have slight differences, are said to show variety.
Notes:
An example of sexual reproduction leading to variety is shown in the diagram below.
Adults
Offspring
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Outcome 9:
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In asexual reproduction, only one individual is needed as a parent.
There is no mixing of genetic information and so no genetic variation in the offspring.
These genetically identical individuals are known as clones.
New plants are produced quickly and cheaply by taking cuttings from older plants.
Key Facts:
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Some living things can produce offspring from a single parent. This is called asexual
reproduction.
Because all the genes in the offspring have come from the same parent, the offspring will
be identical to that parent.
Examples of asexual reproduction are:
- Cuttings taking from plants
- Yeast cells dividing to make new cells.
Gardeners can often grow new plants more quickly by taking cuttings than they can by
planting seeds.
Key Words:
Asexual reproduction - this is a way of reproducing new offspring from only one parent.
Characteristics
- these are features that distinguish one person from another, eg shape
of nose or colour of eyes.
Cutting
- a piece of a plant (often a leaf) that is cut off. It can then be planted in
soil in an attempt to grow a new plant.
Genes
- these are found inside living cells. They carry the information for
making new individuals.
Offspring
- these are the young animals or plants that are produced by the
parent(s) as a result of reproduction.
Notes:
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Outcome 10:
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Darwin’s theory of evolution states that all species of living things have evolved from simple
life-forms that first developed more than three billion years ago.
Evidence to support this theory of evolution is limited to fossil evidence and the similarity of
characteristics between species.
Key Facts:
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
Over millions of years, the appearance of most plants and animals has changed very
slowly.
The very first life-forms on Earth were very simple organisms, often consisting of a single
cell.
These very simple organisms have evolved or changed into more complex plants and
animals.
We can see evidence of this change by studying fossils. These are the remains of plants
or animals that lived millions of years ago. Often these plants and animals have become
extinct, and no more of those species are still alive today.
Key Words:
Billion
Evolution
-
a thousand million, ie. 1,000,000,000.
the process by which living organisms have gradually changed over a
very long period of time.
Extinct
- this means that the species has died out and no individuals of that
species are alive today.
Fossil
- Fossils are the preserved remains or traces of animals, plants, and other
organisms from the remote past.
of chromosomes
or of DNA
is required.
Species No knowledge
- a group
of plants or animals
that have
similar characteristics and which
are capable of reproducing with each other to produce others of their
kind.
Theory
- this is an idea, belief or suggestion to explain something that can be
seen. A theory may be tested by looking for evidence to support it.
Notes:
It is very difficult to give a precise definition of the word species at this level.
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Component 3: Chemistry
Materials from the Earth
Outcome 1:
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All substances are made of atoms.
A substance that is made of only one sort of atom is called an element.
There are about 100 different elements. Candidates should understand that most of the
elements are metal.
Elements are shown in the periodic table.
Key Facts:
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Atoms are the ‘building blocks’ of all materials.
There are about 100 different types of atom. A substance that contains only one type of
atom is called an element. Elements are shown in the periodic table.
Most elements are metals.
Metals can be recognised by their physical properties. These include: the ability to
conduct heat and electricity, a high melting point, high mechanical strength and they
appear shiny.
Some elements are non-metals.
Non-metals can be recognised by their properties. These include: the ability to resist
the flow of heat and electricity through them, and a low melting point.
Key Words:
Atom
Element
-
Metal
-
Non-metal
-
Periodic table
-
26
this is the smallest particle of an element that can exist.
elements are the basic ‘building blocks’ of chemistry. They cannot be
broken down into simpler substances. There are about a hundred
different elements. Atoms of different elements can combine together to
make new substances called compounds.
a material which has certain properties, eg it can conduct heat and
electricity easily. Metals usually have a high melting point and can be
polished to a shiny surface.
a material which has certain properties, eg it does not conduct heat or
electricity easily. Non-metals often have a low boiling point or are brittle
solids.
the 100 or so different elements can be put into a table so that elements
in the same column in the table have similar properties.
Support Book – ELC Science 5948
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Notes:
It is sometimes difficult to distinguish between metals and non-metals. A judgement must be made
after considering many different properties of the material. Even then, it may be difficult. Some
elements such as silicon have some properties of metals and some of non-metals.
Although candidates do not need to know the positions of elements within the periodic table, they
may benefit from seeing the general layout of one.
He
Li
Be
B
C
N
O
F
Ne
Na Mg
Al
Si
P
S
Cl
Ar
Cu Zn Ga Ge As Se Br
Kr
K
Ca Sc Ti
Rb
Sr
Y
Cs
Ba
La
Fr
Ra Ac
V
Cr
Zr Nb Mo
Mn Fe Co
Tc
Ni
Ru Rh Pd Ag Cd
In
Sn Sb Te
Tl
Pb
Bi
I
Xe
Po At Rn
Key:
Metals
Non -metals
Noble gases
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Outcome 2:



When elements react, their atoms join with other atoms to form compounds
Chemical reactions can be represented by word equations.
Candidates should be able to recognise simple compounds of metals and non-metals
from their names, eg sodium chloride, magnesium oxide.
Key Facts:



When a chemical reaction takes place, elements combine together.
Chemical equations can be written in words and/or symbols to represent reactions.
In chemical equations, reactants are written on the left-hand side and products are
written on the right-hand side.
Key Words:
Compound
-
Product
Reaction
-
Reactant
-
Word equation
-
this is a substance formed by the chemical combination of two or more
different elements.
a substance that is made as a result of a chemical reaction.
chemical reactions occur when substances change to produce different
substances.
one of the chemical substances that is the starting point for a chemical
reaction.
a chemical word equation shows on the left-hand side those chemicals
that reacted together (the reactants) and on the right-hand side the new
chemicals that were made in the reaction (the products).
Notes:
Knowledge of chemical symbols or formulae is not required.
A typical chemical reaction between two different elements to form a compound is:
sodium + chlorine  sodium chloride
28
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Outcome 3:



Limestone, mainly composed of the compound calcium carbonate, is quarried and can
be used as a building material.
Limestone is heated with clay to make cement.
Cement is mixed with sand to make mortar and with sand and aggregate to make
concrete. No knowledge of the production process of cement is required.
Key Facts:








Calcium carbonate is a compound.
Limestone is a very useful building material. It can be used in the form of stone blocks
or it can be crushed and used as small pieces (aggregate).
Cement is made by heating a mixture of crushed limestone and clay.
Quarrying limestone may cause damage to the environment, especially by causing air
pollution, dust and noise, and by destroying natural habitats for wild life.
Quarrying can be of benefit by providing raw materials and acting as a source of
employment.
Mortar is used to bind bricks together in buildings.
Cement is used in the making of mortar and concrete.
Concrete is often used instead of brick to make buildings. It can also be used for floors
and pathways.
Key Words:
Aggregate
Calcium carbonate
-
Cement
-
Clay
-
Concrete
Limestone
Mortar
Quarry
-
fine stones, like gravel.
this is a compound formed from the elements calcium, carbon and
oxygen.
a powder made from limestone, clay and other materials. When
mixed with water a chemical reaction takes place and the mixture will
harden.
a natural earthy material that can be moulded when wet, and is often
used for making bricks or pottery.
a mixture of cement, sand and small stones.
a naturally occurring rock. It is mainly calcium carbonate.
a mixture of cement and sand.
an open pit where rocks are dug out of the ground.
Notes:
Support Book – ELC Science 5948
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Outcome 4:




Ores contain enough metal to make it economical to extract the metal.
Unreactive metals, such as gold, are found in the Earth as the metal itself, but most
metals are found as concretes that require chemical reactions to extract the metal.
We should recycle metals to save resources.
Candidates may be required to evaluate the social, economic and environmental
impacts of recycling metals.
Key Facts:






Only a few metals, such as gold, can be found in their natural state in the ground.
Most metals have to be extracted from their ores using chemical reactions.
An ore is rock that contains metal or metal compounds from which the metal can be
obtained economically.
Rocks are only called ores if it is economic to extract the metal from them.
Instead of throwing away metal objects when they are no longer any use, they can be
made into new objects.
A lot of energy is needed to quarry metal ores and to extract metals from their ores. It is
often cheaper to recycle metals.
As well as being cheaper, there are other reasons why recycling metals is a
good thing, such as reducing the amount of waste that we throw away..
There are many effects upon the environment of recycling metals. For
example, the number or size of quarries may be reduced, or the amount
of energy required may be less.
Key Words:
Extract
Metal
Ore
Recycling
Unreactive
-
To take out. In the case of an ore it means to obtain the pure metal from
the rock.
A material which has certain properties, eg it can conduct heat and
electricity easily. Metals usually have a high melting point and can be
polished to a shiny surface.
A volume of rock that contains minerals that can be extracted and
processed economically into useful materials (often metals).
- Taking metal objects that have reached the end of their useful life, melting
them down and using them to make new objects.
-
Means that a chemical is very unwilling to take part in a chemical reaction.
Notes:
The names of the metals which candidates will need to know are:
Aluminium, copper, gold and iron
Knowledge of the names of particular ores is not required.
Recycling of metals has an impact on society in general. For example, the amount of refuse to be
disposed of may be greatly reduced by recycling.
30
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Outcome 5:


Most iron is converted into steels.
Steels are alloys since they are mixtures of iron with carbon and other metals.
Key Facts:





Pure iron is not often used to manufacture items.
Mixing other chemical materials with iron makes substances called steels.
Mixing iron with another substance makes an alloy.
Alloys often have different properties from the metals that they contain.
Different steels can be made to have different properties, depending on what is mixed
with the iron. For example stainless steel is good at resisting corrosion; other types of
steel may be particularly strong.
Key Words:
Alloy
Carbon
-
Iron
-
Mixture
-
Steels
-
a mixture of substances, at least one of which is a metal.
a non-metallic element that can exist in different forms, eg soot,
graphite or diamond.
a metallic element not found in its natural state but which has to be
extracted from a compound in its ore.
when substances are mixed together to make a mixture a chemical
reaction does not take place. The different parts of the mixture can
usually be separated again fairly easily. If the substances do react
together to make a new substance, a compound has been made.
are alloys that always contain iron and carbon and sometimes other
metals as well.
Notes:
Support Book – ELC Science 5948
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Outcome 6:


Most metals in everyday use are alloys.
Pure iron, copper, gold and aluminium are too soft for many uses and so are mixed with
small amounts of other elements to make them harder for everyday use.
Key Facts:





Iron is mainly used to make steel.
Steel is often used as the framework for large buildings, for making pipes and for
making sharp cutting tools.
Copper can be made into alloys such as brass and bronze, which are often used for
items such as water taps and ornaments. Pure copper is a good electrical conductor,
and so is often used for electrical wiring.
Gold is often used for jewellery.
Aluminium is used to make cooking foil, kitchen utensils and for the bodies of cars and
aeroplanes.
Key Words:
Aluminium
-
Copper
-
Gold
-
a silvery white metallic element not found in its natural state but which
has to be extracted from a compound in its ore.
a reddish-brown metallic element that is an excellent conductor of heat
and electricity.
a soft, yellow metallic element that can be found in its natural state in
the ground.
Notes:
Candidates should be able to interpret pie charts. Using pie charts to show the composition of
some alloys may be a good way of introducing them.
32
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Outcome 7:




Copper has properties that make it useful for electrical wiring and plumbing.
The properties of copper are limited to its ability to conduct electricity easily and the
ease with which it can be worked.
Low density and resistance to corrosion make aluminium a useful metal.
No knowledge of the extraction process of aluminium is required.
Key Facts:




Copper is a good electrical conductor. This means that it allows an electrical current to
pass easily through it without losing much energy as heat.
Copper is quite soft. This means that wires and cables made from copper can easily be
bent to turn round corners.
Aluminum is often used to make the bodies of aircraft. Using aluminum means that the
aircraft has a relatively low density.
Aluminum is often used to make window frames for buildings. Aluminum is useful for
this because it does not corrode easily.
Key Words:
Conduct
-
Corrosion
-
Density
-
Plumbing
-
Worked
-
means ‘to allow to pass through’. Metals let both electricity and heat flow
through them easily.
most common metals will slowly undergo a chemical reaction with
substances in the air. This process is called corrosion. Rusting of iron is
an example of corrosion; iron combines with oxygen in the air to make a
new substance.
refers to how heavy an object is for its size. A low density material is one
in which a large amount of it weighs very little.
a system of pipes connected together to carry water. These pipes are
often made of copper.
when a metal is ‘worked’, this means that it is bent or hammered into
different shapes.
Notes:
Candidates should be familiar with some common uses of aluminium and copper.
Support Book – ELC Science 5948
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Outcome 8:




Crude oil is a mixture of a very large number of compounds, and may be found in
deposits underground, eg the oil fields under the North Sea.
Crude oil may be separated into fractions by distillation.
Candidates will not be required to recall the names of any of the fractions.
This process, which takes place in a refinery, can be used to produce a range of useful
fuels and oils.
Key Facts:





Crude oil is formed from organic material which has been buried and altered.
Crude oil is a fossil fuel.
The compounds in crude oil can be separated into useful products.
This separation into useful products is done in an oil refinery.
Petroleum gas (LPG), petrol, kerosene, diesel oil, lubricating oil and bitumen are some of
the fractions that can be obtained from crude oil.
Key Words:
Compound
-
Crude oil
Distillation
-
Fuel
Fraction
Oil refinery
Oilfield
-
34
this is a substance formed by the chemical combination of two or more
different elements.
a natural liquid product used as a raw material by oil refineries.
is a process in which a liquid is heated so that it evaporates. It then cools
and condenses back into a liquid. Because some other substances (often
impurities) that were mixed in with the original liquid do not get distilled in
the same way it can be used as a means of purifying a liquid.
a chemical which can be burnt to release energy.
one of the parts that can be separated from crude oil.
a processing plant where crude oil is separated out into useful products.
a place where there is enough oil to be found underground to make it
worth extracting.
Support Book – ELC Science 5948
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Notes:
The map shows that there are oilfields to be found under the North Sea.
Oil Fields
No details of the names or exact locations of the individual oilfields are required.
The block diagram shows the inputs and outputs of an oil refinery
Crude oil in
Petrol and other
products out
Refinery
A diagram showing more detail of the products may also be useful.
LPG
Petrol
Kerosene
Diesel
Lubricating oil
Crude oil in
Bitumen
N.B. the idea of fractional distillation is not required.
Support Book – ELC Science 5948
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Outcome 9:




Most fuels, including coal, contain carbon and/or hydrogen and may also contain some
sulfur. When they burn energy is released.
The gases released into the atmosphere when a fuel burns completely include carbon
dioxide, water (vapour), and sulfur dioxide if the fuel contains sulfur.
Carbon dioxide causes global warming and sulfur dioxide causes acid rain.
Candidates may be required to evaluate the impact on the environment of burning fossil
fuels.
Key Facts:






When natural gas burns in plentiful supplies of air, carbon dioxide and water are made and
a lot of energy is released.
Increased amounts of carbon dioxide and water vapour in the atmosphere can lead to
global warming.
Increased amounts of sulfur dioxide in the atmosphere can lead to acid rain.
Burning fossil fuels is the most common way in which polluting gases are put into the
atmosphere.
Two of the most common polluting gases are carbon dioxide and sulfur dioxide.
Acid rain can kill living organisms, especially trees and other plants life.
Key Words:
Acid rain
- when sulfur dioxide and other gases such as oxides of nitrogen dissolve
Carbon dioxide
Sulfur dioxide
-
in rain water an acidic solution known as ‘acid rain’ is formed.
an invisible gas which is produced by burning fuels and by respiration.
a harmful, acidic gas often produced when fossil fuels containing
compounds of sulfur are burned.
Notes:
Burning a fuel in a plentiful supply of air is sometimes referred to as complete combustion.
Complete combustion:
Fuel
+
oxygen

carbon dioxide + water
Remember that if candidates are asked to evaluate, they should be able to name an advantage
as well as a disadvantage.
36
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Outcome 10:

When fuels burn in a limited supply of air a poisonous, odourless gas called carbon
monoxide is produced. Solid particles (soot) may also be produced.
Key Facts:




When natural gas burns in a limited supply of air, carbon monoxide is also produced and
there is less carbon dioxide and energy released.
Carbon monoxide is an invisible, poisonous gas.
Carbon monoxide can be produced when fossil fuels such as coal, gas and oil are burned
in rooms where there is not enough ventilation.
Carbon monoxide is also produced by car engines and smoking tobacco.
Key Words:
Carbon monoxide Soot
-
a poisonous gas produced when fuels burn in a limited supply of air.
a form of carbon, usually a black powder.
Notes:
Burning a fuel in a limited supply of air is sometimes referred to as incomplete combustion.
Incomplete combustion:
Fuel + oxygen  carbon monoxide + water
Candidates should be aware of the dangers of using gas fires in a poorly ventilated
room.
They may see notices fixed to portable gas appliances such as this one:
WARNING!
This fire must only be used in a well-ventilated room
Or they may be familiar with carbon monoxide detectors, such as this one:
Support Book – ELC Science 5948
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Component 4: Chemistry
Oils, Earth and Atmosphere
Outcome 1:




Crude oil is a raw material used to make polymers such as poly(ethene), poly(propene) and
PVC.
Polymers are waterproof and resistant to chemicals, so they have many useful applications
Common names of these polymers will be accepted. Knowledge of the names of other
polymers is not required.
Applications include packaging materials and moulded containers.
Key Facts:









Crude oil is used as a raw material to make polythene.
Crude oil can be extracted from the ground.
Crude oil is a complicated mixture of many chemicals. These have to be separated from
each other before they can be of any use.
This separation process is done in an oil refinery.
Polythene has many useful applications because it is waterproof and resistant to chemicals,
eg packaging materials, moulded containers.
Polythene has many properties that make it useful.
Heat makes polythene soften. This is useful because it means that polythene can be
moulded or rolled into sheets.
Polythene is waterproof, and is not affected by most chemicals such as acids and alkalis.
Polythene is used to make many household items.
Key Words:
Crude oil
Moulded
Polymer
-
Polythene
-
38
a natural liquid product used as a raw material by oil refineries.
means that a material can be squeezed into different shapes.
polymers are chemical substances that are made up of many molecules
all strung together to form really long chains.
chemical name poly(ethene), a common plastic which softens on heating
and is unaffected by most chemicals.
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Notes:
The correct chemical name for polythene is poly(ethene). However, this is often called simply
polythene and candidates may use this simpler term.
Polythene is often used for wrapping and packaging, especially of food products. It is also used for
containers that need to be resistant to chemicals, and to make a range of household items, such
as buckets and washing-up bowls.
This is another area in which it may be useful to introduce pie charts, for example to show the
proportions of the output of a refinery that are made into different products.
Support Book – ELC Science 5948
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Outcome 2:


Many polymers are not biodegradable, so they are not broken down by microbes.
This can lead to problems with waste disposal.
Key Facts:




Although polymers are very useful, there are problems about how we get rid of them.
Most polymers will not rot naturally when they are thrown away.
This causes a problem because they can cause litter and can cause landfill sites to become
full quickly.
Items such as polythene bags can be a danger to wildlife.
Key Words:
Biodegradable
-
Incineration
-
Landfill sites
-
Microbe
-
Recycling
-
A biodegradable product has the ability to break down, safely and
relatively quickly, by biological means, into the raw materials of
nature and disappear into the environment.
this is a process of burning rubbish. It can be useful for getting rid of
waste material, but it can often produce toxic gases or greenhouse
gases.
these are sites where waste material can be buried in the ground.
They are often used to dispose of household rubbish.
Microbe is another word for microorganism. This is a microscopic
organism that is too small to be seen with the naked eye, but can be
seen under a microscope. Microbes include bacteria, viruses and
some fungi. Many microbes are very useful to us because they
break down waste products.
as an alternative to burning or burying waste, sometimes it can be
recycled. This may involve using the material again to make a new
object.
Notes:
Candidates should appreciate the problems caused by plastics in litter and that recycling plastics is
difficult because of the many different types of plastic.
Knowledge of plastic waste disposal is limited to landfill sites, incineration, and recycling.
40
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Outcome 3:



Vegetable oils are important foods and fuels as they provide a lot of energy.
Oils do not dissolve in water. They can be used to make emulsions.
Examples of emulsions are limited to salad dressings and ice cream.
Key Facts:





Oils that are obtained from plant material are called vegetable oils.
These oils can be very useful, as they can be used in foods, in burning to provide energy,
or in processing to make new materials.
Oil and water do not mix together to form a solution.
If oil and water are mixed, the oil will eventually float to the surface of the water.
Sometimes this separation can be delayed for a long time. If this can be done, the mixture
is said to be an emulsion.
Key Words:
Dissolve
-
Emulsion
-
Oils
-
Solution
-
Vegetable oil
-
if a substance dissolves in a liquid it will disappear so that it cannot be
seen. For example, when you add sugar to your tea, the sugar dissolves
in the water. Dissolving is a usually physical change and not a chemical
change, as it can usually be easily reversed, for example by evaporating
the liquid.
this is a mixture of two liquids that do not dissolve in each other, for
example oil and water.
are certain types of liquids that do not mix with water. They may be
vegetable or mineral.
a mixture in which one substance is dissolved in another. For example,
when you dissolve salt in water it makes a salt solution.
this is oil which has been obtained from plant material, often the seed.
Notes:
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Outcome 4:


Vegetable oils have higher boiling points than water and so can be used to cook foods at
higher temperatures than by boiling.
Using oil produces quicker cooking and different flavours but increases the energy that the
food produces when it is eaten.
Key Facts:




Water boils at approximately 100 °C.
Most vegetable oils have a boiling point between 150 °C and 300. °C
Oil is rarely boiled for cooking, as it reaches its ‘smoke point’ well before its boiling point.
When raw chips are put into very hot oil, what you see is the water from the chips boiling,
and not the oil boiling.
Key Words:
Boiling point -the temperature at which bubbles of gas start to form within a
that is being heated.
liquid
Notes:
Candidates should know that vegetable oils and fats provide more energy than the same mass
of either carbohydrates or proteins.
42
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Outcome 5:


The Earth’s crust and the upper part of the mantle are cracked into a number of large
pieces, called plates.
Candidates should be familiar with a simple model of the Earth, consisting of a crust,
mantle and core.
Key Facts:



The Earth is made up of three parts: the inside part is called the core, surrounding this is
the mantle, and the surface layer is called the crust.
The Earth’s crust is relatively thin.
The crust and part of the mantle have become cracked to form several large pieces called
plates.
Key Words:
Core
-
Crust
-
Mantle
Plates
-
44
This is the very centre of the Earth. Temperatures here are extremely
hot.
The Earth’s crust is like the skin of an apple, it is very thin compared to
the thickness of the core and mantle. It is only a few miles thick.
The mantle makes up most of the volume of the Earth.
These are large sections of the Earth’s crust that have cracked away from
other parts. These plates are huge, the whole of the Earth’s surface
being split into 8 plates.
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Notes:
This diagram shows a section through the Earth to show the structure.
This diagram shows the Earth’s plates.
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Outcome 6:


Convection currents within the Earth’s mantle cause the plates to move at speeds of a few
centimetres per year. The movements can be sudden and disastrous.
Earthquake and/or volcanic eruptions occur at the boundaries between these plates.
Key Facts:







Part of the mantle is so hot that the rocks in it have become almost like a liquid.
Because the mantle can behave like a liquid, it moves around in a series of convection
currents.
As the mantle moves, it carries the plates around with it. This movement happens
incredibly slowly.
The different plates in the Earth’s crust move in different directions.
This means that the edges of the plates will sometimes be moving away from each other,
sometimes colliding with each other, and sometimes slipping past each other.
It is at the edges of the plates where volcanoes and earthquakes are most likely to happen.
Scientists cannot accurately predict when volcanoes and earthquakes will occur.
Key Words:
Boundary
Convection currents Earthquake
-
Volcanic eruption
-
46
this is the ‘edge’ between two of the plates in the Earth’s crust.
can only occur in liquids and gases. Warm fluid rises and cold
fluid sinks. This circulation is called a convection current.
this is a sudden release of energy in the Earth’s crust. It causes
the whole area to shake violently.
this happens where an opening in the Earth’s crust allows hot,
molten rocks from below the surface to be pushed violently
upwards and released onto the surface of the Earth.
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Notes:
This diagram shows convection currents in the Earth’s mantle.
This diagram shows a volcanic eruption forcing molten rock to the surface.
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Outcome 7:



During the first billion years of the Earth’s existence, there was intense volcanic activity.
This released the gases that formed the early atmosphere and water vapour that
condensed to form the oceans.
The early atmosphere was mainly carbon dioxide.
Key Facts:



The atmosphere contains a mixture of gases.
When the Earth was first formed, these gases were mainly carbon dioxide and water
vapour.
The present day atmosphere contains oxygen which we need for respiration.
Key Words:
Atmosphere
Billion
-
The atmosphere is a layer of gases surrounding the surface of the Earth.
a billion is a thousand million. ie 1,000,000,000.
Notes:
48
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Outcome 8:



Plants and algae produced the oxygen that is now in the atmosphere, by a process
called photosynthesis.
Most of the carbon from the carbon dioxide in the early atmosphere gradually became
locked up in rocks as carbonates and fossil fuels.
Candidates will be required to know the word equation:
Carbon dioxide + water  sugar + oxygen
Key Facts:






Without green plants, we could not live.
By a process called photosynthesis, plants put oxygen back into the atmosphere that we
have used up in respiration.
The atmosphere has changed since it was first formed millions of years ago.
Nowadays there is a lot less carbon dioxide in the atmosphere.
Chemical reactions have taken place, which have turned some of the carbon dioxide into
rocks called carbonates.
Carbon dioxide has also been used by plants for photosynthesis. When these plants have
died, they have formed fossil fuels. This means that the carbon dioxide has not been
released from them yet.
Key Words:
Carbonates
-
Fossil fuel
-
Photosynthesis
-
these are chemical compounds. They are formed when carbon dioxide
reacts with an acid.
a fuel that has been made from the remains of plants and animals that
died millions of years ago.
is a process carried out by green plants. In the presence of sunlight,
plants can use carbon dioxide and water to make food. This process
also releases oxygen into the atmosphere.
Notes:
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Outcome 9:

The proportions of different gases in the Earth’s atmosphere are about four-fifths (80%)
nitrogen, about one fifth (20%) oxygen, with small proportions of other gases, including
carbon dioxide, water vapour and noble gases.
Key Facts:





Most of the air is nitrogen. Nitrogen is unreactive.
The second most common gas in the air is oxygen.
Oxygen is needed for burning and respiration.
There are only tiny amounts of other gases in the air.
Noble gases do not combine with other elements in chemical reactions.
Key Words:
Carbon dioxide
Oxygen
Water vapour
Noble gas
Helium
Unreactive
-
an invisible gas which is produced by burning fuels and by respiration.
a gas found in the air.
water which has evaporated into the air to form an invisible gas.
gases such as helium and neon. They are very unreactive
one of the noble gases. It has a very low density.
does not take part easily in chemical reactions.
Notes:
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Outcome 10:


Nowadays, the release of carbon dioxide by burning fossil fuels increases the level of
carbon dioxide in the atmosphere.
Candidates may be required to evaluate the effect of human activities on the
atmosphere.
Key Facts:

.

.
.


Burning a fossil fuel releases carbon dioxide and water vapour into the atmosphere
Carbon dioxide and water vapour are both ‘greenhouse gases’.
Greenhouse gases can lead to global warming, where the average temperature of the
Earth’s atmosphere becomes greater.
Global warming can lead to climate changes.
Climate changes caused by global warming can involve the increased risk of flooding in
certain parts of the world. In other parts of the world it may lead to droughts.
Global warming may lead to the melting of ice in the polar regions, and so to increased sea
levels.
Global warming could have a severe effect on the habitats of wild animals and plants,
leading to the extinction of some species.
Key Words:
Burning
-
is sometimes called combustion. It is a chemical reaction in which a fuel
combines with oxygen to release heat energy.
Notes:
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Component 5: Physics
Energy transfer and efficiency
Outcome 1:


All bodies emit and absorb infrared radiation.
The hotter an object is the more infrared energy it radiates in a given time.
Key Facts:








A ‘body’ can be any object that has mass.
All ‘bodies’ will both give out and take in thermal radiation.
‘Hotter’ means that it is at a higher temperature.
Infrared radiation is often called heat or thermal radiation.
Thermal radiation can transfer heat energy across long distances.
Thermal radiation can transfer energy across a vacuum. It is by this method that heat from
the Sun reaches the Earth.
When energy is transferred it is moved from one place to another.
When energy is transformed it is changed from one type to another.
Key Words:
Absorb
Emit
Energy
Radiation
Radiate
Thermal energy
Transfer
- to take in.
- to give out.
- energy is what allows us to do work, eg when moving things. There are
many different kinds of energy, including electrical, heat (thermal), light
and sound energy.
- the transfer of energy from one place to another by means of invisible
waves.
- to emit or give out energy as an electromagnetic wave.
- the correct scientific word for heat energy.
- moving energy from one place to another or changing it from one form to
another.
Notes:
All bodies will emit and absorb thermal radiation at the same time.
If a body is hotter than its surroundings, it will be emitting radiation at a faster rate than it is
absorbing it.
If a body is colder than its surroundings, it will be absorbing radiation at a faster rate than it is
emitting it.
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Outcome 2:



Dark, matt surfaces are good absorbers and good emitters of infrared radiation.
Light, shiny surfaces are poor absorbers and poor emitters of infrared radiation.
Light, shiny surfaces are good reflectors of infrared radiation.
Key Facts:




Infrared (thermal) radiation is the transfer of energy by electromagnetic waves, and no
particles are involved in the transfer.
The rate at which a surface emits or absorbs thermal radiation depends upon:
- the type of surface
- the colour of the surface.
Dull, black surfaces are good at transferring thermal radiation. This is why car radiators are
painted dull black – it allows them to lose heat quickly.
Shiny, white surfaces are poor at transferring thermal radiation. This is why athletes who
have just finished a marathon are often given a shiny silver cloak to wrap around them – it
prevents them from losing heat too quickly.
Key Words:
Absorber
Emitter
Matt
Shiny
-
an object that is taking in heat energy.
an object that is giving out heat energy.
dull, not shiny.
polished, with a reflective surface.
Notes:
No definition of the term electromagnetic wave will be required.
Candidates should know that radiation is the method by which thermal energy travels from the Sun
to the Earth. Other examples of thermal radiation include electric radiant heaters and fires.
A flask is a good way in which to illustrate how knowledge of the different types of surface can be
used to control heat flow.
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Outcome 3:


The use of kinetic theory to explain the different states of matter.
The particles of solids, liquids and gases have different amounts of energy.
Candidates should be able to recognise simple diagrams to model the difference between
solids, liquids and gases.

Key Facts:
 The three states of matter are: solid, liquid and gas.
 Solids have a fixed volume and a fixed shape.
 Liquids have a fixed volume but no fixed shape.
 Gases have neither a fixed volume nor a fixed shape. They expand to take up as much
space as there is available.
 If you give enough thermal energy (heat) to a solid it will eventually melt and become a
liquid.
 If you give enough energy to a liquid it will eventually evaporate and become a gas.
Key Words:
Kinetic theory
-
Solid
-
Liquid
-
Gas
-
Thermal energy -
a theory that says that all material is made up of tiny particles. These
particles move.
 in solids, the particles vibrate but do not change places.
 in liquids, the particles move with more energy and can change
places.
 in gases, the particles dash around at high speed.
a material in which the particles are closely packed and usually in a
regular pattern.
a material in which the particles are closely packed but not in any
definite or fixed pattern.
a material in which the particles are spread out well apart from each
other. Most of the volume of a gas is empty space.
the correct scientific word for heat energy.
Notes:
The diagrams show the arrangement of particles in the three states of matter.
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Outcome 4:


Transfer of energy by conduction, convection, evaporation and condensation involves
particles.
No knowledge of the mechanism of how this transfer takes place will be required.
Key Facts:
 Thermal energy (heat) can be moved from one place to another. Normally it will go from
a hot object to a colder object.
 Conduction is the way in which heat can travel through solids. Metals are good
conductors of heat and non-metals are good insulators of heat.
 Convection can only occur in liquids and gases. Warm fluid rises and cold fluid sinks.
This circulation is called a convection current.
 Evaporation occurs when a liquid becomes warm enough to change into a gas.
 Condensation is the reverse of evaporation.
 A knowledge of when and where conduction and convection take place can help us to
reduce the amount of wasted energy, eg by insulating our homes.
 Heat will flow faster if there is a bigger temperature difference.
 This means that by turning down the thermostat on the central heating we can reduce the
rate at which heat is lost from our homes.
Key Words:
Conduction
-
Conductor
Condensation
Convection
-
Evaporation
Insulator
Thermal energy Transfer
-
the process by which heat travels through solids, the energy being
passed from particle to particle.
a material which allows conduction to take place easily.
the process by which a gas can change to a liquid by means of cooling.
the process by which heat may be taken from one place to another by a
liquid or gas circulating.
the process by which a liquid can change to a gas by means of heating.
a material which does not allow conduction to take place easily.
the correct scientific word for heat energy.
moving energy from one place to another.
Notes:
‘Heat’ is a very difficult concept to define with scientific accuracy at this level.
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Outcome 5:
 The factors that affect the rate of evaporation and condensation.
 Candidates should know that evaporation causes a cooling effect.
Key Facts:
 Evaporation occurs when particles in a liquid gain enough energy to escape and become
a gas. This lowers the amount of energy remaining in the liquid, which becomes colder.
This is what causes the cooling effect of evaporation.
 Evaporation occurs most rapidly when

the temperature is high

the surface area from which the liquid can evaporate is large

there is a wind blowing over the evaporation surface.
This is why washing dries more quickly if it is spread out on the washing line and the
weather is warm and windy.
 A good example of the cooling effect of evaporation is sweating.
Key Words:
Temperature
-
a measure of how hot or cold something is.
Notes:
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Outcome 6:


The rate at which an object transfers energy by heating depends on:

surface area

the material from which the object is made

the nature of the surface with which the object is in contact.
Candidates should be able to explain animal adaptations in terms of energy transfer, for
example relative ear size of animals in cold and warm climates.
Key Facts:
 Heat will flow faster if there is a bigger temperature difference.
 Heat will flow faster if there is a bigger surface area.
Key Words:
Rate
-
is a measure of how quickly something happens.
Notes:
Candidates will not be required to do calculations involving surface to volume ratios.
This desert fox has very
large ears to help it to
lose heat and stay cool.
Support Book – ELC Science 5948
This arctic polar bear
has very small ears to
help it to retain heat and
stay warm.
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Outcome 7:
 The bigger the temperature difference between a body and its surroundings, the faster
the rate at which energy is transferred by heating.
Key Facts:
 Heat will flow faster if there is a bigger temperature difference.
 This means that by turning down the thermostat on the central heating we can reduce the
rate at which heat is lost from our homes.
Key Words:
Temperature
-
a measure of how hot or cold something is.
Notes:
Energy costs money and resources are limited.
By lowering the temperature in our homes, we will reduce the rate at which heat is lost.
Reducing the rate at which heat is lost from our homes saves us money.
Candidates will probably have plotted cooling curves, such as the one below.
Temperature
Time
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Outcome 8:
 Heating and insulating buildings.
 Candidates should be familiar with different methods of conserving energy in the home.
 U-values measure how effective a material is as an insulator.
 The lower the U-value, the better the material is as an insulator.

 Knowledge of the U-values of specific materials is not required, nor is the equation that
defines the U-value.

Key Facts:

In the UK we are usually trying to keep heat inside the house.
In other countries in the world, the problem is often trying to keep heat out of the house.
Methods of insulating the home include:

for windows, double glazing or the use of blinds or curtains

for walls, cavity wall insulation, thermal (plasterboard) lining or rendering

for floors, carpet and/or underlay or laying wood on top of concrete

for roofs, the use of fibreglass insulation

for chimneys, the use of a cowl

for gaps around doors and windows, the use of draught excluders or sealing mastic

for the whole house, turning down the thermostat on the central heating or the use
of individual thermostatic radiator valves.


Key Words:
U-value
60
-
is a measure of how quickly thermal energy (heat) will flow through a
material. The larger the U-value, the faster the flow of heat.
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Notes:
In the U.K., it is important to reduce the heat that is lost from our homes. There are several ways
of doing this.
Cavity walls are one method of building house walls. Two walls are built, with a small gap or cavity
in between. This gap is often filled with special foam or fibreglass in order to reduce heat losses.
The diagram below shows some of the main ways in which heat is lost from a house. Candidates
would not be expected to recall such numerical information in an examination. However, they may
be provided with the information and asked to interpret or process it.





Fibreglass loft insulation reduces heat lost through the roof.
Fibreglass or foam cavity wall insulation reduces heat lost through the walls.
Double-glazing or the use of curtains reduces heat lost through the windows.
Carpet and underlay reduces heat lost through the floor.
Draught excluders around doors reduce heat lost through draughts.
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Outcome 9:
 When energy is transferred, only part of it may be usefully transferred, the rest is
‘wasted’.
 Wasted energy is eventually transferred to the surroundings, which become warmer.
 The wasted energy becomes increasingly spread out and so becomes less useful.
Key Facts:
 When energy is transferred or transformed, not all of it will end up in the place where we
want it or in the form that we want it. Some energy is usually wasted.
 Energy is always conserved. ‘Wasted’ energy does not disappear without trace but is
converted into a non-useful form, usually heat.
 Examples of energy being wasted as heat occur in:

light bulbs, where only a small proportion of the electrical input energy is turned into
useful light

machines that have moving parts.
Key Words:
Wasted energy -
energy that is transformed into a form that is not useful.
Notes:
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Outcome 10:

The greater the percentage of the energy that is usefully transformed in a device, the more
efficient the device is, eg the comparison between filament bulbs and fluorescent tubes.
No calculations involving efficiency will be required.
Candidates may be required to describe the intended energy transfers and the main energy
wastages that occur in a range of appliances.


Key Facts:

.
A filament bulb contains a piece of thin wire (the filament). When electricity passes through
this it gets very hot and gives out light.
A fluorescent tube does not contain a filament. Instead it contains a gas.
.
Key
Words:
Efficiency
-
Filament bulb
Fluorescent tube
-
a measure of how much of the input energy is changed into a
useful form at the output.
the conventional style of light bulb.
a type of energy saving lamp.
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Notes:
A fluorescent tube contains a gas. When an electrical discharge it passed through the gas it
causes the coating on the inside of the tube to give out light energy.
Candidates could compare the advantages and disadvantages of ‘long life’ domestic bulbs.
Filament bulb
Fluorescent
bulb
Other examples could include the ‘energy efficiency’ stickers fixed to domestic appliances such as
washing machines and fridges.
This radio is only 1% efficient at producing sound energy.
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Component 6: Physics
Electricity and waves
Outcome 1:


The domestic electricity meter measures the amount of electrical energy used in “units”
(kilowatt-hours).
No calculations of kilowatt-hours will be required, nor will any calculations involving the cost
of electricity be required.
Key Facts:



The electricity meter records how much electricity has been used, in units.
Users are charged for the number of units used.
To find the number of units used, you take away the previous reading from the present
reading.
Key Words:
Electricity meter
-
this is a meter supplied by the electricity company and fixed in the house.
It measures the amount of electrical energy supplied in ‘units’ .
Unit
- a measure of the amount of electrical energy supplied. Each number
‘clocked up’ by the meter is one unit.
Electrical energy - energy is what allows us to do work, eg when moving things. There are
many different kinds of energy, including electrical energy.
Notes:
Below is an example of an electricity meter and how to work out the units used.
Previous reading (units)
45300
Present reading (units)
45700
To find the number of units used, deduct the previous reading from the present reading.
Present reading
Previous reading
Number of units used
Support Book – ELC Science 5948
=
=
=
45700
45300
400
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Outcome 2:




The amount of electrical energy a device transfers depends on how long the appliance
has been switched on and its power.
The power of an appliance is measured in watts (W) or kilowatts (kW).
No calculations of the amount of electrical energy will be required.
Candidates should be aware that heating devices generally have a higher power rating
than other electrical devices.
Key Facts:






Electrical devices transform energy, ie. change it into a different form, eg light or heat
or movement.
The faster they transform energy, the higher their power rating.
Kettles, fires, toasters and immersion heaters are all examples of electrical heating
devices.
A watt is a very small unit of power.
Because the watt is so small, power is often measured in kilowatts.
One kilowatt equals one thousand watts.
Key Words:
- this is the rate at which energy is changed from one form to another, ie.
the amount of energy transferred in a certain time.
Electrical energy - energy is what allows us to do work, eg when moving things. There are
many different kinds of energy, including electrical energy.
Transform
- to change energy from one type to another.
Power
Notes:
Candidates should appreciate that the higher the power rating of a device, the faster the rate at
which it transfers energy.
Candidates may be required to compare the relative amounts of energy transformed by devices of
different power ratings switched on for differing amounts of time.
For example, which of the following would transform the most amount of energy if they were all
turned on for 10 minutes?
Answer: the 2000 watt toaster
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Outcome 3:


In some power stations an energy source is used to heat water. The steam produced drives
a turbine that is coupled to an electrical generator.
No knowledge of the internal construction of these units will be required.
Key Facts:





Electricity can be generated using a variety of different energy sources.
Whatever energy source is used, a rotating generator actually makes the electricity.
All generators are turned by a turbine.
The turbine may be driven by steam, air or water moving past the turbine blades.
Steam is produced by heating water.
Key Words:
Generator
-
Power station
-
Turbine
-
a mechanical device that changes kinetic energy (energy of movement)
into electrical energy.
this is a place in which another form of energy is changed into electrical
energy, usually for supply to the mains electricity supply.
A system of blades on an axle (like a propeller) that can be made to turn
by air, steam or water being made to flow onto them.
Notes:
Candidates may be required to interpret a flow diagram, ie. Water is heated in a boiler to produce
steam, steam at high pressure forces the blades of a turbine to rotate and this then rotates the
moving part of a generator. The generator transforms movement energy into electrical energy.
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Outcome 4:



Energy sources include:
the fossil fuels coal, oil and gas, which are burned to heat water or air
•
uranium and plutonium, when energy from nuclear fission is used to heat water.
No knowledge of the fission process required.
Key Facts:




Coal, oil and gas are called fossil fuels. This because they were formed millions of years
ago from living material.
Some materials are naturally radioactive. These emit high-energy radiation.
Uranium and plutonium are examples of materials that are naturally radioactive. They are
used in nuclear reactors.
The heat to make steam from water can also be produced by a radioactive source in a
nuclear reactor.
Key Words:
Nuclear
Fission
Radioactive
Uranium
Plutonium
-
concerning the nucleus of an atom.
the splitting of the nucleus of an atom into smaller pieces.
a radioactive material is one that can emit very high energy radiation.
an element which is naturally radioactive.
an element which is naturally radioactive.
Notes:
The diagram shows a block plan for a nuclear power station.
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Outcome 5:

Renewable energy sources include:
• biofuels, that can be burned to heat water
• water and wind that can be used to drive turbines directly
• solar cells that can be used to produce electricity directly from the Sun’s radiation
• geothermal energy. In some volcanic areas, hot water and steam rise to the surface.
The steam can be tapped and used to drive turbines.
Key Facts:








Biofuels include materials such as straw, or ethanol produce from sugar cane.
Water falling from a height can be made to turn the turbine blades in a hydroelectric
scheme.
The wind causes air to flow past the turbine blades of a wind turbine causes them to
turn.
It is the visible light part of the Sun’s radiation that operates a solar cell.
Solar cells are only capable of generating small amounts of electrical energy.
Solar cells are particularly useful in remote areas where there is no mains supply of
electricity.
Deep down below the surface, the Earth is very hot.
We can use this heat energy to heat water to make steam for turbines.
Key Words:
Geothermal energy - energy that is provided by hot rocks beneath the surface of the ground.
Hydroelectric
- a way of producing electrical energy by allowing water from a high
reservoir to run downhill and drive a turbine linked to a generator.
Renewable
- a source of energy that can easily be replaced and is not ‘used up’.
Solar cell
- this is a device which can turn light energy directly into electrical energy.
Notes:
The pie chart shows the estimated sources of bio fuels in 2022.
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---------------------------------------------------------------------------Candidates should be familiar with the concept of wind farms and hydroelectric schemes.
A wind turbine
A hydroelectric scheme
Examples of practical applications of solar cells include traffic signs and parking meters, or
regions remote from a mains supply.
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---------------------------------------------------------------------------Examples of situations where only a very small current is required include, eg cameras,
calculators.
The diagram shows a geothermal power station.
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Outcome 6:




Using different energy resources has different effects on the environment.
Knowledge is limited to the release of substances into the atmosphere, noise and visual
pollution, the production of waste materials, and the destruction of wildlife habitats.
Candidates should be able to compare and contrast the particular advantages and
disadvantages of using different energy sources to generate electricity.
Comparisons are limited to those between fossil fuels, nuclear and renewable resources.
Key Facts:














Atmospheric pollution is often caused by gases given off when fuels are burned.
Carbon dioxide is produced when fossil fuels are burned, and can lead to global warming.
Sulfur dioxide is often produced when fossil fuels are burned, and can lead to acid rain
formation.
Green plants use carbon dioxide for photosynthesis. Cutting down trees reduces the
amount of carbon dioxide that is reabsorbed from the atmosphere.
Methane is a waste product produced by cows when digesting their food.
Both of these gases are ‘greenhouse’ gases and may lead to global warming.
Nuclear radiation is produced when the nucleus of an atom breaks down.
Although nuclear radiation can be very useful, it can also be very dangerous.
If our body receives too much nuclear radiation, we can develop cell damage and cancers.
Noise pollution is often caused by large wind turbines.
Visual pollution may be caused by building large power stations or erecting wind turbines.
There are many different sources of energy that we can use to generate electricity.
All of these different methods have some good points and some bad points.
We often have to make choices as to how we should generate electricity. In doing so we
have to weigh up all the good points and the bad points.
Key Words:
Atmospheric pollution
Environment
Habitat
Visual pollution
Fossil fuels
-
Carbon dioxide
Methane
-
Global warming
Greenhouse effect
-
Nuclear radiation
-
this is caused by smoke and gases released into the atmosphere.
the surroundings around where you live.
the natural environment in which an organism lives.
refers to things which are unsightly or not pleasing to look at.
these are fuels like coal, gas and oil. They were formed millions of
years ago from plants and animals that died.
a gas produced when fossil fuels are burned.
a gas produced by the digestive systems of cows and other animals,
and by breakdown of organic waste eg in landfill sites.
a rise in the average temperature of the Earth’s atmosphere.
is the rise in temperature that the Earth experiences because certain
gases in the atmosphere (water vapour, carbon dioxide and
methane, for example) trap energy from the sun. Without these
gases, heat would escape back into space and Earth’s average
temperature would be colder.
radiation that comes from the nucleus of an atom.
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Notes:
The advantages and disadvantages of different methods of making electricity are given in the table
below.
Type of energy source
Advantages
Disadvantages
Well-tried technology.
Fuels are easy to use.
Fossil fuels
Nuclear
Wind turbines and hydroelectric
A large amount of energy
is released from a small
amount of fuel.
No chemical pollution.
Running costs are lower.
No thermal or chemical
pollution.
Supplies will run out
Causes chemical pollution, eg
by producing carbon dioxide
and thermal pollution, that lead
to global warming
Danger of radiation escaping.
Problems with waste disposal
of material as the waste can be
highly radioactive.
Supplies may fluctuate, eg the
wind does not always blow.
They may spoil the appearance
of the landscape.
No knowledge of how the greenhouse effect causes global warming is required.
Some materials are naturally radioactive. These emit high-energy radiation.
Uranium is an example of a material that is naturally radioactive. It is used in nuclear reactors.
Radioactivity is a natural process.
We are continually subjected to a very low level of radiation. This is called ‘background radiation’.
Background radiation comes mainly from space and from rocks in the Earth’s crust.
Exposure to radioactivity can cause cell damage and cancer
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






Waves transfer energy.
Waves may be either transverse or longitudinal.
Electromagnetic waves are transverse and form a continuous spectrum.
All types of electromagnetic waves travel at the same very high speed through a vacuum
(space).
Sound waves are longitudinal and mechanical waves may be either transverse or
longitudinal.
Candidates should know the order of electromagnetic waves within the spectrum, in terms
of energy, frequency and wavelength.
Knowledge of the magnitude of the speed will not be required.
Key Facts:
 There is a whole family of waves called the electromagnetic spectrum. It contains gamma



rays, X-rays, ultraviolet rays, visible light, infrared rays, microwaves and radio waves.
The speed of electromagnetic waves is reduced if they travel through a material.
The electromagnetic spectrum is continuous but the waves within it can be grouped into
types of increasing wavelength and decreasing frequency.
No quantitative values of frequency or wavelength will be required.
Key Words:
Electromagnetic waves Frequency
-
Magnitude
Spectrum
Vacuum
-
Wavelength
-
a group of waves that possess many similar properties.
They are all capable of carrying energy.
means how often a wave passes a certain point (think of the
frequency of a bus service). It is measured in how many complete
waves (cycles) pass a particular point each second. The scientific
term for “cycles per second” is hertz (Hz).
size.
the whole band of electromagnetic waves.
a region in which there are no particles of air or any other
substance.
the length of a wave from the top of one crest to the top of the
next.
Notes:
Candidates should be able to recognise a diagram of a transverse wave, and be able to identify the
wavelength, measured in metres. They should understand that frequency is the number of wave
cycles passing a given point each second, and is measured in Hertz.
Support Book – ELC Science 5948
75
---------------------------------------------------------------------------Notes:
The diagram shows a typical transverse wave. Electromagnetic waves are transverse waves.
One wavelength
Wave travels this way, carrying
energy
The diagram shows the electromagnetic spectrum.
Increasing
frequency
Gamma
rays
X-rays
Ultraviolet
waves
Visible
light
Infrared
waves
Micro
waves
Radio
waves
Increasing
wavelength
X-rays pass easily through soft flesh but are stopped by hard bone. This makes them suitable for
taking pictures of broken bones, which would normally be invisible beneath the flesh.
76
Support Book – ELC Science 5948
---------------------------------------------------------------------------Outcome 8:


Radio waves, microwaves, infrared and visible light can be used for communication.
Candidates will be expected to be familiar with situations in which such waves are typically
used, eg
•
radio waves, television and radio (including Bluetooth)
microwaves, mobile phones and satellite television
•
infrared remote controls
•
visible light photography
Key Facts:








Radio waves are used to transmit signals for radio, television, radar and
telecommunications.
They are at the long wavelength end of the electromagnetic spectrum.
Microwaves have a shorter wavelength than radio waves.
Microwaves can pass through the Earth’s atmosphere and are used to send information to
and from satellites and within mobile phone networks.
Some microwaves are used for communication, eg mobile phones.
Some microwaves are used for heating, eg in a microwave oven.
Although all of the different types of electromagnetic wave can be useful to us, there are
dangers if we expose ourselves to too much of them.
Infrared and visible light can be used to send signals along optical fibres and so travel in
curved paths.
Key Words:
Hazard
Infrared
Microwave
-
Optical fibre
-
Radio
-
Radar
-
Satellite
Visible light
-
a danger or disadvantage.
the energy of these waves is often called ‘heat’.
some types of microwave are used in microwave
cookers, others are used for communication, eg mobile
phones or radar.
a very thin strand of glass. Visible light and infrared
waves can be sent along this fibre. The fibre acts rather
like a pipe, carrying the waves inside.
a means of communicating sound messages by
converting them first into electromagnetic waves.
a method used to detect aircraft and ships by reflecting
electromagnetic waves from them.
a man-made object which can orbit the Earth.
these are the waves that we can detect with our eyes.
Notes:
Radio waves are used for radio and television, microwaves for mobile phones, infrared for remote
controls, burglar alarm sensors, and thermography, visible light for seeing and for use in cameras
and telescopes.
Support Book – ELC Science 5948
77
---------------------------------------------------------------------------Notes:
The table below gives some of the uses and associated hazards of each type of electromagnetic
wave.
Type of wave
Gamma rays
Use
Treatment of cancer patients




Photographing broken bones
Security scanning at airports
Heating in microwave cookers
Communication, eg mobile
phones
Ultraviolet



Sun-tan beds
Detecting forged notes
‘secret’ identity marking
Visible light


Enables us to ‘see’ things
Used by plants in photosynthesis
Infrared
Also known as ‘heat’ radiation, so
used for warming
Radio waves
TV and radio transmissions
X rays
Microwaves
Hazard
Overexposure may cause cell damage and
cancers
Overexposure may cause cancers, hence
the need for radiographers etc to be shielded
 Leakage from microwave cookers
causing cancer
 Some concerns over prolonged use of
mobile phones that may affect brain cells.
Special concern regarding children,
whose brains are still developing, as yet
unproven
Ultraviolet in sunlight may cause skin cancer,
hence the need for sun-screen creams
Very bright light can damage the eyes;
therefore we should never look directly at the
Sun
Over exposure can damage
the skin, eg sunburn
Some concern regarding development of
cancers in people living very close to highpower transmitters – as yet unproven
Light and infrared rays can be made to turn corners by passing them along the inside of glass
fibres.
Ray of light
Glass fibre
Applications of optical fibres could include the use of endoscopes in the medical profession and the
use of infrared signals in computer networking.
Satellites can be used to transmit signals around the curvature of the Earth.
78
Support Book – ELC Science 5948
---------------------------------------------------------------------------Outcome 9:



Reflection.
The angle of incidence is equal to the angle of reflection.
Echoes are reflections of sounds.
Key Facts:


All waves can be reflected when they hit a suitable surface.
Light waves travel in straight lines.
Key Words:
Angle of incidence
Angle of reflection
Echo
Incident ray
Reflected ray
Reflection
Normal
-
the angle between the incident ray and the normal.
the angle between the reflected ray and the normal.
the repetition of a sound caused by reflection of sound waves
is the ray of light going in towards the mirror.
is the ray of light reflected away from the mirror.
a change of direction of a wave when it meets a surface.
is a construction line at 90° to the reflecting surface.
Notes
The diagram shows a ray of light hitting a mirror.
Support Book – ELC Science 5948
79
---------------------------------------------------------------------------Outcome 10:



Scientists are able to find out about the Universe by measuring the different types of
radiation given out by the Sun and other stars.
The ‘Big Bang’ theory states that the Universe began from a very small initial point.
Candidates will be expected to know that a process known as red-shift, in which the
apparent wavelength of radiation from stars changes as they move away from us, has
helped to support the ‘Big Bang’ theory.
Key Facts:
.
 Scientists have been able to make a good estimate as to the age of the Universe by
. studying radiation from the stars.

Partly this has come from studying “red shift”. If a star is moving away from the Earth,
some of the lines in the spectrum from the star appear to be shifted towards the red end of
the spectrum. By measuring the amount of shift, scientists can find out how far away the
star is. Because most of the stars that we can see show red shift, this is evidence that the
universe is expanding.

Key Words:
Big Bang
Red Shift
-
Star
-
.
Sun
Universe
-
a theory about the origin of the Universe.
a process by which the apparent wavelength of radiation from stars
changes as they move away from us.
an enormous ball of very hot gases. Unlike planets, stars give off their
own light.
the star at the centre of our solar system.
all the material that exists.
Notes:
80
Support Book – ELC Science 5948
----------------------------------------------------------------------------
Index
Biology
Action
Adapted
Addictive
Aerobic
Algae
Antibiotic
Asexual reproduction
Automatic
Bacteria
Balanced diet
Billion
Bloodstream
Cannabis
Carbohydrate
Carbon dioxide
Cell
Characteristics
Chlorophyll
Chromosomes
Compete
Contraceptive
Coordinated
Cutting
Cytoplasm
Diet
Drug
Egg
Environment
Evolution
Extinct
Fat
Fertility
Fitness
Fossil
5
18
8
20
19
11
23
5
9
6
24
12
8
6
36
19
21
19
21
15
14
12
23
21
6
8
13
18
24
18
6
14
7
24
Support Book – ELC Science 5948
Genes
Glands
Hormones
Ingest
Inhibit
Mates
Mature
Menstrual cycle
Microorganism
Nucleus
Nutrients
Offspring
Oral
Organism
Penicillin
Photosynthesis
Protein
Pulse rate
Pulse
Pupil
Radiation
Red blood cell
Reflex action
Secreted
Sexual reproduction
Species
Stimulate
Survival
Target organ
Territory
Theory
Toxin
Variety
Virus
White blood cell
21
12
12
10
14
16
14
13
20
21
15
23
14
19
11
19
7
7
5
4
19
10
5
12
22
24
14
17
12
16
24
9
22
9
10
81
----------------------------------------------------------------------------
Chemistry
Acid rain
Aggregate
Alloy
Aluminium
Atmosphere
Atom
Billion
Biodegradable
Boiling point
Boundary
Burning
Calcium carbonate
Carbon dioxide
Carbon monoxide
Carbon
Carbonates
Cement
Clay
Compound
Concrete
Conduct
Convection currents
Copper
Core
Corrosion
Crude oil
Crust
Density
Dissolve
Distillation
Earthquake
Economic
Element
Emulsion
Environmental
Extract
Fossil fuel
Fraction
Fuel
Gold
82
36
29
31
30, 32
36,48
26
48
40
42
46
36
29
36, 48
37
36
49
29
29
28
29
33
46
32
44
33
34, 38
44
33
41
34
46
30
26
41
30
30
36, 49
34
34
30
Helium
Incineration
Iron
Landfill sites
Limestone
Mantle
Metal
Microbe
Mixture
Mortar
Moulded
Noble gas
Non-metal
Oil refinery
Oilfield
Oils
Ore
Oxygen
Periodic table
Photosynthesis
Plates
Plumbing
Polymer
Polythene
Product
Quarry
React
Reactant
Recycling
Social
Solution
Soot
Steels
Sulfur dioxide
Unreactive
Vegetable oil
Volcanic eruption
Water vapour
50
40
31
40
29
44
26, 30
40
31
29
38
50
55
34
34
41
30
49
27
49
44
33
38
39
35
29
28
28
30, 40
30
41
37
31
36
30
41
47
50
Support Book – ELC Science 5948
----------------------------------------------------------------------------
Physics
Absorb
Absorber
Angle of incidence
Angle of reflection
Atmospheric pollution
Big Bang
Carbon dioxide
Condensation
Conduction
Conductor
Convection
Echo
Efficiency
Electrical energy
Electricity meter
Electromagnetic waves
Emit
Emitter
Energy
Evaporation
Fission
Fluorescent tube
Fossil fuels
Gas
Generator
Geothermal energy
Global warming
Greenhouse effect
Hazard
Hydroelectric
Infrared
52
53
79
79
73
80
73
55
55
55
55
79
63
66
65
75
52
53
60
55
68
63
73
50
67
69
73
73
77
70
77
Support Book – ELC Science 5948
Magnitude
Methane
Microwave
Nuclear radiation
Nuclear
Optical fibre
Plutonium
Power station
Power
Radar
Radiate
Radio
Radioactive
Rate
Reflected ray
Reflection
Renewable
Satellite
Solar cell
Solid
Spectrum
Star
Sun
Temperature
Thermal energy
Transform
Turbine
Universe
Uranium
U-value
Vacuum
Visible light
Visual pollution
Wastage
Wavelength
75
73
77
74
74
78
68
67
66
77
52
77
74
57
79
79
69
78
69
54
75
80
80
56
55
66
67
80
68
60
75
75
74
63
75
83
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84
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