) Which activity would you do to prove that the temperature of a substance must reach
the combustion point of that substance in order to ignite it?
Answers
Answer:
Some substances, like magnesium catches fire and burns with a dazzling white flame when heated in air. Similarly, when a piece of per is brought near a candle flame, it burns, producing heat and light. The charcoal and coal bums in air producing carbon dioxide, heat and light.
Air or oxygen which helps in burning is called supporter of combustion and the chemical reaction which takes place with the release of heat and light energy is called combustion.
A chemical process in which a substance reacts with oxygen to give off heat is called combustion.
The substances which undergo combustion are known as combustible substances. It may also be called a fuel.
Sometimes, heat is accompanied by light, either as a flame or as a glow, during combustion.
Fuel may be solid, liquid or gas. A combustion reaction maybe written as-
(a) Charcoal burns in air to give carbon dioxide and heat.
C + O2 → CO2 + Heat
(b) Methane bums in air forming carbon dioxide, water and heat.
CH4 + 2O2 → CO2 + 2H2O + Heat