Question

What are the characteristics of a chemical reaction ?

Answer 1

Change in colour
Change in state
Change in temperature
Evolution of gas
Formation of precipitate

Answer 2

In chemical reaction the composition of the reactants or substances will be changed and can not be recovered.In other words breaking of bonds,formation of bonds and reconstruction of bonds will take place in a chemical reaction and thus forming a new substane.In chemical reaction there may be change in colour,state,temperature of the substance and there may be chance of forming precipitate and gas evolved