POLYTECHNIC OF NAMIBIA
SCHOOL OF HEALTH AND APPLIED SCIENCES
DEPARTMENT OF NATURAL AND APPLIED SCIENCES
QUALIFICATION:
QUALIFICATION CODE:
LEVEL:
4
COURSE:
BASIC SCIENCE
COURSE CODE:
BSC410S
DATE:
16TH JUNE 2014
SESSION:
08H00
DURATION:
3 HOURS
MARKS:
130
QUESTION PAPER
Examiners: Dr. Jeya Kennedy and Dr. Marius Mutorwa
Moderator: Dr.Habauka Kwaambwa
THIS QUESTION PAPER CONSISTS OF 7 PAGES
(EXCLUDING THIS FRONT COVER, PERIODIC TABLE)
READ THESE INSTRUCTIONS FIRST
1.
Write in dark blue or black pen on the answer paper.
2.
You may use a soft pencil for any diagrams or rough working.
3.
Write neatly and clearly.
4.
The number of marks is given in brackets ( ) at the end of each question or part question.
5.
No books, notes and other additional aids are allowed.
6.
Only a scientific calculator is allowed.
7.
The Periodic Table is provided (attached).
8.
Answer ALL Questions.
9.
Answers must be in SI units.
0
SECTION A: BIOLOGY – TOTAL MARKS: 50
QUESTION 1
Fill in the blank spaces
[6]
1.1 The __________ is the smallest unit of life.
(1)
1.2 In incomplete metamorphosis, young animals that look like the ___________ hatch
from eggs.
(1)
1.3 A complex of interconnected food chains in an ecosystem is called a (an) _______.
(1)
1.4 When sucrose is hydrolyzed, it yields ________ and _____________.
(1)
1.5 In the winemaking process, _________________ is the name given for the crushed
grapes and juice.
(1)
1.6 Animals store carbohydrates in the form of ____________.
(1)
QUESTION 2
[18]
2.1 What are the 7 characteristics of living things?
(3.5)
2.2 List the three domains and six kingdoms of organisms.
(4.5)
2.3 What are the two classes of flowering plants, and how can one distinguish between
them?
(5)
2.4 What is the difference between a reptile and an amphibian and give 2 examples of
each?
(5)
QUESTION 3
[6]
3.1 What are Abiotic factor and name any two of them?
(2)
3.2 Define producer and consumer.
(2)
3.3 What types of symbiotic relationships are represented in the picture (a) and (b)?
(a)
(b)
(2)
1
QUESTION 4
[8]
4.1 What are the three types of carbohydrates? Give an example of each.
(3)
4.2 Which type of protein is insoluble in water?
(1)
4.3 Which class of vitamins has the potential to be toxic? And why?
(2)
4.4 Which vitamin is called clot master?
(1)
4.5 What role does calcium play in the body?
(1)
QUESTION 5
[12]
5.1 Describe the process is known as malting in beer production.
(4)
5.2 How is sweet wine produced?
(2)
5.3 Define the term homogenisation.
(1)
5.4 State the steps involved in gasohol production.
(5)
SECTION B: CHEMISTRY – TOTAL MARKS 40
QUESTION 6
[10]
6.1 A certain element is described in the following manner:
The element is a silvery-white lustrous metal. It melts at 649 oC and the density is 1.738
g/cm3. The substance burns in air, producing an intense white light. It reacts with
chlorine to give a brittle white solid. It is a good conductor of electricity.
Which of these characteristics (represented in bold) are physical properties, and which
are chemical properties?
(3)
6.2 Classify each of the following diagrams as a pure substance or mixture. Explain your
reasoning for each diagram.
(2)
i)
ii)
2
6.3 Name the process when the following changes in the state of matter occur and indicate
whether the change in state is an endothermic or exothermic process.
(2)
a. Gas into Solid
b. Liquid into Solid
c. Solid into Gas
d. Gas into Liquid
6.4 Indicate which physical separation technique you would use to separate the following
mixtures.
(2)
a. oil from water
b. sugar dissolved in water
6.5 Arrange the different states of matter (solid, gas, liquid) for a given substance in terms
increasing intermolecular forces.
Question 7
(1)
[10]
7.1 Provide definitions for the following terms used in measurements.
(2)
a. Absolute zero
c. Accuracy
7.2 Perform the following mathematical operations and express each of the answers to the
correct number of significant figures or where applicable, to the correct number of
decimal places.
(4)
a. 264.42 + 238.547 – 135.0
b. 81.04 x 0.010
c. 4278 x 1.005
d. (6.222 – 2.20) / 2.5
7.3 How many significant figures does each of the following measurements have?
(2)
a. 800000
b. 350.670
c. 0.00340
d. 320001
7.4 The temperature of an acetone/dry ice mixture was recorded to be 210.2 K. Convert the
temperature into Degrees centigrade (oC) and Fahrenheit (oF).
(2)
Given: oF = (1.8 x oC) + 32
3
Question 8
[12]
8.1 Elements are pure substances consisting of one kind of an atom. What is the difference
between an ion and an isotope for a particular element?
(2)
8.2 Use the clues (marked in bold) and the periodic table provided to identify the element
being described and fill in the missing information (a – e).
(6)
The element has 4 valence electrons and it has 14 electrons in a neutral atomic state.
The element is found in period ____ (a) _____. The name of element is ____ (b) ____
and its symbol is ____(c) _____. The element has __ (d) _____ protons and __(e)
___neutron in the nucleus. The element is classified as a (n) ___ (f) ____.
8.3 What is meant by a corrosion reaction and state one method of preventing such a
reaction from taking place?
(1)
8.4 Name the three metal elements which are classified as the iron triad.
(1)
8.5 Determine whether each of the following statements is true or false. If false, correct it or
state why the statement is false.
(2)
a. Elements in the same period have the same number of valence electrons and have
similar chemical properties.
b. During ionic bonding, non-metals tend to donate their valence electrons and form
positively charged ions.
Question 9
[8]
9.1 In table format, list two uses for sulphuric acid and two uses for calcium oxychloride. (4)
9.2 Fill in the products formed in the following reactions:
a. Ca + H2SO4
____________ + ________
b. 2HCl + Na2CO3
__________ + ________+_________
(2)
4
9.3 Complete the following table by providing the name and formula of the inorganic
compound.
(2)
Chemical name
Formula
_______(a)_______
NaHCO3
Magnesium hydroxide
____(b)____
SECTION C: PHYSICS – TOTAL MARKS 40
QUESTION 10
[10]
10.1 The height (in cm) for 30 students in a physics class was determined as follows:
Height in cm
139.5 – 149.5
149.5 – 159.5
159.5 – 169.5
169.5 – 179.5
179.5 – 189.5
189.5 – 199.5
Frequency
5
8
7
5
3
2
a. Use the data in the table to draw a column graph of the Frequency against the
Height.
(6)
b. From the histogram drawn in (a), determine:
i.
How many students have heights between 159.5 – 169.5?
ii.
How many students have heights less than 159.5?
iii.
How many students have heights more than 169.5?
iv.
What percentage of students have heights between 149.5 – 179.5?
Question 11
11.1 Define the term Power.
(4)
[10]
(1)
11.2 List two advantages and two disadvantages of using biomass or biofuel as a renewable
energy source.
(4)
5
11.3 A student with a mass of 8200 g stands at the top of a hill of height 0.4 Km (Position A),
as shown in the diagram below. Note: Answers should be in SI units
a. What is the student’s gravitational potential energy at the top of the hill?
Note: Gravitational acceleration (g) = 9.8 m.s-2
b. Assuming that energy is conserved and there is no friction, what will the
student’s velocity be at the bottom of the hill (position B)?
(2)
(3)
Question 12
[6]
12.1 What is the meaning of the term alternating current (AC).
(1)
12.2 Determine from the circuit below:
a. the combined resistance in parallel.
b. the total resistance in the circuit
c. the main current in the circuit
d. the potential difference across AB.
6
12.3 How does a fuse act as a safety device in an electric circuit or plug?
(1)
Question 13
[6]
13.1 Amongst gamma, beta and alpha radiation, which is a:
a. high energy electron?
b. electromagnetic wave?
c. positively charged helium nucleus?
(3)
13.2 Strontium-90 has a half-life of 28 years. Calculate the amount of strontium left after
224 years, if the original amount of strontium is equal to 25.50 grams.
(3)
Question 14
[8]
14.1 Define the following terms:
a. Newton’s first law
(2)
b. Longitudinal wave
14.2 List three effects that a force, when applied, can have on an object moving at a
constant velocity.
(3)
14.3 If the speed of a sound wave is 2.98 m.s-1, determine the wavelength produced in
micrometers (µm) by a radio station broadcasting at a frequency of 220 KHz.
(3)
7