4.1
Properties of Matter
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Time
PRESCRIBED LEARNING OUTCOMES
45–60 min
• conduct investigations into properties of matter
Key Ideas
KNOWLEDGE
Matter can be described
using observable properties.
Matter can be described
using measurable properties.
• the observable properties of matter include colour, texture, and state
• the measurable properties of matter include density, melting point,
and freezing point
Vocabulary
SKILLS AND ATTITUDES
•
•
•
•
•
• demonstrate curiosity, skepticism, creativity, open-mindedness,
accuracy, precision, honesty, and persistence as important scientific
attributes
property
states
melting point
freezing point
boiling point
Skills and Processes
Observing
Communicating (sharing)
Lesson Materials
per student
• various materials from
around the classroom, such
as textbooks, pencils,
paper, and lamps
Program Resources
BLM 0.0-5 Two-Column Table
BLM 4.1-1 Property Tree
SM 4.1 Properties of Matter
Nelson Science Probe 7
Web site
www.science.nelson.com
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ICT OUTCOMES
• work cooperatively using information technology tools
• use a variety of information technology tools to create, modify, explore,
and present electronic documents that express ideas or concepts
• apply the principles of good design when developing electronic
documents
SCIENCE BACKGROUND
Properties of Matter
• Matter is anything that has both
mass and volume. The properties of
matter are the characteristics that
we use to describe and/or identify
matter. Properties of matter can be
physical or chemical. Typical physical
properties include state, colour,
texture, odour, lustre, clarity, and
taste. Additional properties include
hardness, strength, crystal form,
density, solubility, viscosity,
malleability, ductility, elasticity,
melting point, and boiling point.
Density, solubility, melting point, and
boiling point are covered in the
student book. Other properties are
described below.
– Hardness is a measure of the
resistance of a solid to being
scratched or dented. A harder
material will scratch or dent a
softer one. A diamond stylus can
be used to cut a large sheet of
glass into different sizes.
– Strength is a measure of the
resistance of an object to being
broken. A stronger material will be
harder to break.
– Crystal form is the form of many
minerals in which you can see a
definite structure of cubes or
blocks with a regular pattern. When
you look closely at salt crystals, you
can see that they are tiny cubes.
– Solubility is the ability of a
substance to dissolve in a solvent,
such as water. Salt is described as
soluble and pepper is described as
insoluble. Drink mixes, for example,
contain powdered substances that
are soluble in water. Solubility is
covered in Chapter 6.
– Viscosity is a measure of how
easily a substance flows—the
thicker the liquid, the more viscous
it is. Oil is “thicker” than water; it
flows more slowly than water
when you pour it. Honey is another
example of a viscous liquid.
– Malleability is a measure of how
easily an object can be shaped.
Gold can be hammered into thin
sheets, so it is malleable. If a solid
is malleable, it can be hammered
or bent into different shapes.
Aluminum foil is malleable, which
makes it useful for wrapping food
as it cooks. Many materials, glass
for example, are not malleable.
Instead of flattening out when
hammered, they shatter.
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– Ductility is a measure of how
easily an object can be pulled or
drawn into a wire. One of the
reasons copper is used for
electrical wiring is that it can be
drawn out into long, thin wires.
– Elasticity is the ability of an object
to return to its original shape after
being stretched, bent, or
compressed. A rubber band is
elastic because it returns to its
original shape after being pulled
apart. Poles used during pole
vaulting are also elastic.
Physical Properties
• Density, melting point, and boiling
point are characteristic physical
properties, which means that they
can be used to identify a substance.
They are unique to a substance. For
example, only water has a boiling
point of 100°C and a melting point of
0°C. Therefore, any substance that
boils at 100°C must be water.
• A physical property is a characteristic
of a substance that may help to
identify it. Unlike a chemical
property, a physical property does
not involve a substance becoming a
new substance. For instance, colour
is a physical property. A substance
simply has a certain colour: its colour
has no relationship to the
substance’s ability to change into
new substances.
Chemical Properties
• Chemical properties refer to the
ability of matter to undergo a
(chemical) change because of its
composition. Such changes occur
during reactions with water, acids, or
other substances, or during
combustion or burning. For example,
hydrogen has the ability to ignite and
explode under the right conditions,
and iron rusts when it reacts with
oxygen. We say that hydrogen is
combustible or has the property of
combustibility. Other substances are
flammable, meaning that they will
burn.
• Chemical reactions result in different
substances being formed. For
example, iron oxide, formed during
rusting, has different properties than
the original iron metal. When
gasoline burns, new substances
(carbon dioxide, water) and energy
are produced.
• Some chemical reactions, such as
rusting, occur slowly, while others,
such as combustion, occur more
quickly.
Uses of Properties of Matter
• The properties of matter determine
how a substance is used. For
example, a liquid with high viscosity
and a high boiling point would make
a good lubricant for an automobile
engine.
• Matter can be grouped as metals
and non-metals. Metals are suitable
for different uses because of their
special properties. People have used
metals for thousands of years. Today,
many different mixtures of metals,
called alloys, are used. Whatever the
purpose, whether for airplane parts,
the bottom of cooking pots, or
braces for teeth, the metal chosen
has properties that are appropriate
for the job. For example, materials
for airplane parts must have low
density, high strength, and the right
balance of rigidity and flexibility.
TEACHING NOTES
Related Resources
1 Getting Started
CRC Handbook of
Chemistry and Physics.
• Check for Misconceptions
– Identify: Students may have the misconception that anything that
cannot be seen or observed directly with the senses is not matter.
For example, some students may not consider air to be matter
because it cannot be seen.
– Clarify: Students are probably familiar with the three states of matter
(solid, liquid, and gas). Discuss how there is matter that cannot be
directly observed (e.g., air), but we use indirect evidence (e.g., the
effect of moving air) and/or measurements (e.g., air pressure) to
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Matter can be described using properties.
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confirm that it has mass and takes up space. If necessary, use a
simple demonstration (e.g., pushing an inverted glass into water) to
illustrate that air occupies space, or has volume.
– Ask What They Think Now: Ask students, Can you think of anything
that doesn’t have mass and volume, or that can’t be described using
observable or measurable properties?
• Discuss with students how we use properties to classify matter in our
daily lives. Ask students what classification systems are used (e.g.,
clothing: shirts, pants, coats; music: CDs by artist name or by genre;
eating utensils: forks, spoons, knives, etc.)
• As an introductory activity, have students sort themselves according
to their “properties” (e.g., gender, hair colour, types of clothing) until
each student is in a group by himself/herself. In searching for a
possible solution, students will learn a great deal about which
properties make them the same as or different from other students.
Starting with the entire class, have students decide how to divide
themselves. (This may require teacher assistance, and teacher
direction can start students thinking by first dividing the class by
gender.) Once students are divided, the two groups should move to
opposite sides of the room. Have each group then divide itself into
two groups based on another property, which need not be the same
for all groups. This process of dividing will continue until each
person is by himself or herself. Encourage students to record the
properties they used to categorize or classify themselves.
• Hand out BLM 4.1-1 Property Tree and have students fill in the
chart. Ask students to trace the path they took (e.g., divide into
males and females, divide again into dark hair and light hair, or
wearing glasses and not wearing glasses) as they were separated by
properties.
• After the activity, discuss which properties are the most general (left
side of tree) and which properties are most specific (right side of the
tree). Ask, Which properties make students unique, original, and special?
• Discuss the five senses and how they relate to matter. Ask students
for examples of things that cannot be detected with all five senses.
For example, air cannot be seen or tasted. Is air matter? It is
important for students to understand that some matter cannot be
sensed directly. In such cases, we rely on indirect observations and
measurements to describe and identify matter.
2 Guide the Learning
• Read the first paragraph of Section 4.1, Properties of Matter, aloud.
Discuss the five senses. Suggest that some of the most important
parts of our body are designed to explore the world around us
(e.g., sight through our eyes, sound through our ears).
• For students who need additional support with reading in this
section, use SM 4.1 Properties of Matter.
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• It is not easy to observe the gaseous state of water at room
temperature. It cannot be seen, smelled, felt, tasted, or heard. You
have to use indirect observations (e.g., condensation on a cold
object) to obtain evidence that there is gaseous water in the air.
• Have students complete Try This: Observe Properties.
TRY THIS: OBSERVE PROPERTIES
Purpose
• Students will observe some common classroom items and describe the
observable properties of those items.
Suggested Answers
• Student answers will vary. A possible student observation might be “I spy
something that is a solid, white, and is used for writing on chalkboards.” The
answer is chalk.
• As students read the section, have them follow Reading and
Thinking Strategies: Determine Meaning of Key Scientific and
Technical Terms. Have students read the section, noting the bolded
and highlighted terms. They should use the Glossary to check the
meaning of bolded terms if necessary.
• The concepts of solubility and density are introduced in the first
paragraph under Properties You Can Measure, but students are
informed that these concepts will be addressed later in the unit. The
terms are not introduced in the student book, so it is advisable not
to introduce them at this point.
• Students may be confused when they read that there are two
temperatures at which a substance changes state, because they will
also read that there are three state-change points (the melting point,
freezing point, and boiling point).
• Definitions of melting point and freezing point are given in the
student book, but it is not stated until the end of the freezing point
definition that the freezing point of a substance is the same as the
melting point. Students should understand that freezing point is
used to describe the change of state from liquid to solid, and
melting point is used to describe the change of state from solid to
liquid. These details are explained fully in Section 5.1, but students
should be introduced to this idea here.
• Water can change from a liquid to a gas without a rise in the
temperature to the boiling point. Students are already familiar with
the concept and the term evaporation, which is also addressed in
Section 5.1.
• Students do not normally think of the boiling points of solids (like
metals), but the water example in the student book is a good
introduction to the idea that all matter that is solid at room
temperature has a melting point and a boiling point, even though
some of these melting and boiling point temperatures are extremely
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high or extremely low (e.g., copper melts at 1084°C and boils at
2336°C, and diamond melts at 3550°C and boils at 4827°C).
Likewise, all matter that is gaseous at room temperature has a
freezing point and a boiling point (e.g., nitrogen freezes/melts at
–201°C and boils at –194°C).
• Ask students, How can you lift an ice cube with a piece of thread
without getting under the cube? Tell them that salt will help with this
challenge, and that the thread will lift the ice. Ask students, What do
you think is happening to the melting point of the ice where the salt is
sprinkled? Have students observe the amount of melting on the
cube. Is the puddle getting larger or staying the same? What is
happening to the concentration of salt water as the ice melts? Wait a few
moments before trying to lift the cube with the thread. Ask
students, What do you think caused the melted ice to freeze again over
the thread? Remind students that salt water has a lower freezing
temperature than fresh water. Explain that the ice melts where the
salt is added, but since the rest of the ice is still below 0°C, the
water freezes again over the thread. Therefore, ice can be lifted with
the thread. Ask students, At what temperature does salt water boil?
Add salt to a beaker of water and heat the solution on a hot plate.
Take temperature readings of the thermometer every few minutes.
Ask students to predict how high the temperature will rise for the
salt water.
3 Consolidate and Extend
• Explain to students that water molecules are held tightly together,
but when salt is added to the water, the water molecules become
attracted to the salt, thus requiring more heat energy to transform
the water from a liquid state to a gaseous state. Adding more salt to
the water increases the boiling temperature of the salt solution.
• Emphasize that melting point and boiling point are properties of
matter that can help to identify a substance. While a specific melting
point may not be unique to a single element or compound, it does
narrow the number of possibilities, so that another observable
property or measurement (e.g., boiling point) can lead to a positive
identification of a substance. For example, if an unknown liquid
boils at 100°C and freezes at 0°C, then you can be reasonably sure
that the liquid is water.
• Assign the Check Your Understanding questions. Students can use
BLM 0.0-5 Two-Column Table to complete question 1.
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CHECK YOUR UNDERSTANDING—SUGGESTED ANSWERS
Technology Connections
1. Student charts about properties they can observe using their senses, and
properties they can observe using simple measurements, should look similar to
the chart below.
Using your senses
Using simple measurements
colour
taste
texture
odour
lustre
clarity
state
melting point
freezing point
boiling point
At Home
2. a) When a substance reaches its melting point, the solid form of the substance
changes to a liquid.
b) When a substance reaches its freezing point, the liquid form of the
substance changes to a solid.
c) When a substance reaches its boiling point, the liquid form of the substance
changes to a gas.
States of Matter
You can also use your five senses to observe whether a substance is
a solid, a liquid, or a gas. These are called the states of matter.
A substance may be found in all three states. For example, water can
be found as a solid (ice), a liquid (water), or a gas (water vapour in
the air), depending on the temperature. You can easily observe the
state of a substance at room temperature.
TRY THIS: OBSERVE PROPERTIES
Skills Focus: observing, communicating
Play “I spy” with a partner using the observable properties of matter. Use
the format, “I spy something that is (pick a state) and is (pick one or more
properties from Table 1) …” For example, “I spy something that is a solid,
and is blue and shiny. What is it?”
Check with your teacher before you taste anything other
than your own lunch.
Properties You Can Measure
Some properties can be determined using simple tests and
measurements. For example, you could put a substance in water to
see if it dissolves. You could also put a variety of substances in water
to see which ones float and which ones sink. Later in this unit, you
will measure properties of matter using both of these tests.
LEARNING TIP
The key vocabulary words
in this section are illustrated
with photographs.
Melting and Boiling Points
One of the properties of matter that
can be measured is the temperature at
which a substance changes state. Most
substances have two temperatures at
which they change state.
The melting point of a substance
is the temperature at which the solid
form of the substance changes to a
liquid (Figure 2). For example, water
changes from solid ice to liquid water
at 0°C. Thus, the melting point of
solid water (ice) is 0°C.
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Unit B Chemistry
Have students work with a
partner to create a poster
using a computer graphics
program that lists the
various properties of
matter and uses text
boxes to provide a brief
explanation and example of
each property.
Figure 2
Have students conduct
Try This: Observe
Properties with their
family members and
explain to their families
the properties that can be
observed by the senses.
Reading and Thinking Strategies: Determine
Meaning of Key Scientific and Technical Terms
• Direct students’ attention to the words in bold found
in this section. Explain that when words, such as
properties and states, are written in bold and
highlighted, they are important vocabulary words that
need to be learned. Words bolded in this manner are
intended to highlight important ideas and to focus the
attention of the reader. These words can also be found
in the Glossary at the back of the student book. The key
vocabulary words in this section are illustrated with
photographs.
• Ask students what strategies they use when they do
not know the meaning of a highlighted science word.
Work with them to develop a list of suitable strategies
such as the following:
– Use the words around the highlighted word to figure
out the meaning.
– Look for clues in the illustrations, photos, and
captions on the page.
– Look up the word in the Glossary.
– Ask someone else what he or she thinks it means.
The melting point of ice is 0°C.
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Meeting Individual Needs
Extra Support and ESL
• Pair students in mixed-ability teams so that students are able to draw
from each others’ individual strengths.
• To practise using the terminology in context, have students describe
the physical properties of various familiar substances. ESL students can
also make a visual dictionary illustrating in both pictures and words
the meaning of various properties of matter to reinforce terminology
and support comprehension. This visual dictionary can be used and
added to throughout each science unit.
• For students who need additional support with the reading in this
section, use SM 4.1 Properties of Matter.
Extra Challenge
• Challenge students to list the properties of a material needed for a
specific application (e.g., a spacesuit, a CD, or fuel in a car) and then
identify a material that might work.
ASSESSMENT FOR LEARNING
What To Look For in Student Work
Suggestions for Teaching Students Who Are Having Difficulty
Evidence that students can
• describe matter using observable properties
(e.g., colour, texture, state)
• make observations (e.g., identify, through
observation, the properties of matter)
• describe matter using measurable
properties (e.g., melting, freezing, and
boiling points)
• display data in tables
• use technical language correctly
(property, states, melting point, freezing
point, boiling point)
• contribute to group efforts (e.g., I Spy)
Limit the number of properties students are asked to observe. Allow students to
communicate in whichever way they feel most comfortable (i.e., writing, speaking).
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