CHAPTER 4 COMBUSTION AND FLAME
When a substance reacts with oxygen to give off heat, the process is called combustion. The substance is called combustible substance or a fuel.
The lowest temperature required for a substance to catch fire is called its ignition temperature.
The substances which have low ignition point are called inflammable substances.
Controlling fire: To control fire, the oxygen supply to the fire has to be cut off.
Types of combustion:
When a substance burns and a sudden evolution of heat, light and sound takes place, it is called an explosion.
The different zones of a candle flame are:
A fuel is a substance which is a source of energy. The properties of a good fuel are:
The amount of heat energy produced on complete combustion of 1 kg of a fuel is known as its calorific value. Unit of calorific value is kilojoule per kg (kJ/kg).
HARMFUL EFFECTS OF BURNING FUELS