Name: ______________________
Class: ______
Grade 7
Module 2
Chemical properties
and Chemical Reactions
Mark
Module checked
Date:
____
10
Comment:
Miss Liza
Dippenaar
Date: _________________
Objective: _____________________________________________
_____________________________________________________
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Checking prior knowledge:
Physical or Chemical Change? Indicate with a ‘P’ or a ‘C’ which type
of change is taking place.
1. ____________ glass breaking
2. ____________ hammering wood together
3. ____________ a rusting bicycle
4. ____________ melting butter
5. ____________ separate sand from gravel
6. ____________ bleaching your hair
7. ____________ frying an egg
8. ____________ squeeze oranges for juice
9. ____________ melting ice
10. ____________ mixing salt and water
11. ____________ mixing oil and water
12. ____________ water evaporating
13. ____________ cutting grass
14. ____________ burning leaves
15. ____________ fireworks exploding
16. ____________ cutting your hair
17. ____________ crushing a can
18. ____________ boiling water
Fill in the Blanks:
____________ properties can be observed without chemically changing matter.
____________ properties describe how a substance interacts with other
substances. ____________ have definite shapes and definite volumes.
____________ have indefinite shapes and definite volumes. ____________
have
indefinite shapes and indefinite volumes.
Phase changes are ____________ changes. ____________ point is the
temperature at which a liquid turns to a solid. It is also equal to the
____________ point which is the temperature at which a ____________ turns
to a ____________. ____________ point is the temperature at which a liquid
turns to a gas, and ____________ point is the temperature at which a gas turns
to a liquid. Occasionally, a solid turns directly into a gas without turning into a
liquid first. This is called ____________.
Label these properties as chemical (C) or physical (P). Be
certain to know the definition of each of these properties.
combustibility _____
malleability _____
weight _____
failure to react _____
ductility _____
texture _____
density _____
tendency to corrode _____
volume _____
melting point _____
odor _____
flammability _____
Signs of a chemical change:
1) Change in color
2) Change in odor
3) Production of heat
4) Fizzing and foaming
5) Sound given off
6) Light given of
Assessment – Chemical changes
Date: ___________________
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1)
In your own words, what is a chemical change?
________________________________________________
________________________________________________
2)
Give 2 examples of a chemical change.
________________________________________________
________________________________________________
3)
For each of the following, state whether it is a chemical change
or a physical change.
Physical change/chemical change
Physical change/chemical change
Physical change/chemical change
Physical change/chemical change
Mini- Class Project
Your task is to describe the properties and purposes of some common objects.
Some of the properties used to describe common materials such as food, clothing,
writing materials and sports equipment are strong, hard, fluffy, solid, smooth,
soft, liquid, bends, floats, shiny, sinks, translucent, opaque, flexible, sticky,
light, runny or heavy.
Here’s an example of a school cap.
Purpose (what it has to do)
Protect your face from the sun
Change size to fit your head size
Materials
Cotton
Properties
Flexible
Plastic
Light
Velcro
Cool
Soft
In each box below, draw a common object and then describe its purposes, materials
and properties.