Answer;
No, sometimes it just causes a physical change, such as ice melting to water.
Explanation;
-The difference between a physical reaction and a chemical reaction is composition. In a chemical reaction, there is a change in the composition of the substances in question; in a physical change there is a difference in the appearance, smell, or simple display of a sample of matter without a change in composition.
Heating a substance may cause a physical change or a chemical change. For example melting ice to water, involves supplying heat to change ice into water which is a chemical change.
-On the other hand, an example of decomposition reactions are chemical reactions which involves supplying heat to a substance; for example decomposing copper (II) nitrate which yields, copper (ii) oxide, nitrogen (iv) oxide and oxygen gas, is chemical reaction.