Asked in Chemistry
Why does a match burn?
April 18, 2010 6:08PM
How does a match work
Although you may not know it, striking a match starts a chemical reaction. There are two types of matches: safety matches and "strike anywhere" matches. A safety match can only light when someone strikes it against the striking surface on the side of the match box. A "strike anywhere" match can be lit by striking the match on anything solid. A "striking surface" is made of sand, powdered glass, and a chemical called "red phosphorus". The head of a safety match is made of sulfur, glass powder, and an oxidizing agent. An oxidizing agent is a chemical that takes electrons from another chemical. When a chemical loses electrons we say it has been oxidized. An oxidizing agent is necessary to keep a flame lit. Oxygen gas is a common oxidizing agent. A simple test for oxygen is to hold a red hot (no flame) piece of wood in a tube of gas that might be oxygen. In oxygen things will burn much faster than in air, and the wood will burst into flame.
When a match is struck on the striking surface of its box, the friction caused by the glass powder rubbing together produces enough heat to turn a very small amount of the red phosphorus into white phosphorus, which catches fire in air. This small amount of heat is enough to start a chemical reaction that uses the oxidizing agent to produce oxygen gas. The heat and oxygen gas then cause the sulfur to burst into flame, which then catches the wood of the match to catch on fire.
A "strike anywhere" match works in a similar way, but instead of phosphorus being on a striking surface, it is added to the head of the match. You can tell the difference between the two types of matches by looking at the colors of the match heads. A safety head is only one color, but a "strike anywhere" match is two colors: one for the phosphorus, and one for the oxidizing agent.