Question

A. tick the most appropriate answer.
1.chemical chains are the result of observation or release of.
a . heat energy only
b . light energy only
c . sound energy only
d . some kind of energy

2. chemical change involves.
a . change of state only
b . change of colour only
c . change in state as well as composition.
d . none of these.

3 a physical change is a
a . temporary change
b . permanent change
c . temperature change which can be reversed.
d. none of these

4. an example of physical changes is
a . burning of wood
b . magnetisation of iron
c . photosynthesis by plant
d . digestion of food

5. an example of a chemical change is .
a . exposing photographic film to sunlight
b . tearing of paper
c . melting of butter
d . formation of clouds.
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Answer 1

. heat energy only

b . light energy only

c . sound energy only

d . some kind of energy