Combustion Basics
What is combustion?
A chemical reaction with oxygen that produces heat and light.
Name one common fuel used in everyday life.
coal, petrol, natural gas, LPG, charcoal.
What is a combustible substance?
A substance that can catch fire and burn.
Which gas is necessary for combustion?
Oxygen
What do people mainly use fuels for?
Heating, cooking, energy production, and transportation.
Give one example of an incombustible substance.
Glass, sand, stone, water, etc
Why does a candle stop burning when covered with a glass?
Because the oxygen inside the glass is used up.
What are the main products when hydrocarbons burn completely?
Carbon dioxide and water.
Why do materials like brick or concrete not burn?
Because they do not react with oxygen and have very high ignition temperatures.
Why do substances burn more strongly in pure oxygen than in air?
Because air contains only about 21% oxygen, while pure oxygen provides much more oxygen for the reaction.
Why are gasoline and LPG called flammable substances?
Because they catch fire easily and have a low ignition temperature.
Why are brick and concrete commonly used to build houses?
Because they are incombustible and safer in fires.