Question

define a) complete combustion amd b) incomplet combustion

Answer 1

Complete combustion means combustion in which there is enough required oxygen

Incomplete combustion means a combination in which there is oxygen is not enough.

Hope it helps you....

Answer 2

a) Combution That occours in presence of sufficient amount of oxygen is complete Combution
It results in Blue Flame
it is not luminous
b) Combution That occours in lack of oxygen is incomplete Combution.
It results in yellow or orange flame
It is luminous