Question

. (a) What is meant by a chemical reaction ? Explain with the help of an example.
(b) Give one example each of a chemical reaction characterised by :
(1) evolution of a gas
(it) change in colour
(ii) formation of a precipitate
(iv) change in temperature
(u) change in state.​

Answer 1

Answer:

in this ans.1,2,3,4 are correct and

the last one is not a chemical reaction