(a) What is a chemical reaction?

(b) State the conditions necessary for a chemical change or reaction.

Define the following terms:

(a) Chemical change

(b) Chemical bond

(c) Effervescence

(d) Precipitate

Define :

(a) Photochemical reaction

(b) Electrochemical reaction.

Give one example in each case.

Give an example of each of the following chemical changes.

(a) A photochemical reaction involving 1. silver salt 2. water

(b) A reaction involving 1. blue solution 2. formation of a dirty green precipitate

(c) Two gases combine to form a white solid.

(d) Two solids combine to form a liquid.

(e) A reaction where color change is noticed.