This document defines and provides examples of physical and chemical changes. A physical change is a temporary change where the composition of a substance does not change and can be reversed through physical means, such as melting or ringing a bell. A chemical change is permanent, forms new substances with different compositions and properties, is irreversible, and involves a gain or loss of energy, such as burning paper or ripening fruit.

2.  It is a temporary change in which no new
substance is formed and can be reversed by
simple physical means.

3.  (i) It is a temporary change.
 (ii) There is a change in physical properties
of a substance.
 (iii) The composition of the substance does
not change.
 (iv) No new substances are produced.
 (v) This change can be easily reversed.
 (vi) There is no energy change.
 (vii) There is no change in mass.

4.  Melting of wax
 Melting of butter
 Ringing of an electric bell
 Expansion and contraction of substances
 sublimation of iodineItorigin

5.  It is a permanent change in which the
original substances give rise to new
substances having different compositions
and properties. It is irreversible and is always
accompanied by energy change.

6.  It is a permanent change.
 New substances are produced.
 The compositions of the substances change.
 This change can not be reversed.
 There is a gain or loss of energy.

7.  Burning of paper
 Baking of potatoes
 Ripening of a fruit
 Burning of phosphorus