Question

When C burns in excess air, it gives a blue coloured flame whereas when same C burns in limited air, colour of flame changes. Give reason.

Answer 1

A blue gas flame indicates complete combustion. Red or yellow gas flames may be a sign of incomplete combustion. With hydrocarbon flames, such as gas, the amount of oxygen supplied with the gas determines the rate of combustion. This is the most important factor in determining the colour of the flame.