Question

Why does the matchstick burn on rubbing it on the side of the matchbox?

Answer 1

Hint: When we rub two rough surfaces with each other, heat generated due to friction. Due to this friction, there is an initiation of chemical transformation.

Complete answer:
The striking surface of the matchbox is made rough by adding some powdered glass. The match head is also rough.
Red phosphorus is present on the striking surface of the matchbox. Potassium chlorate is present on the head of the matchstick. When you rub the head of the matchstick on the striking surface of the matchbox, some heat is generated due to the friction. This heat breaks a small part of the red phosphorus chain. After that some red phosphorus transforms into white phosphorus. White phosphorus is a highly volatile chemical and ignites in the air.
When some heat is generated, potassium chlorate releases oxygen through thermal decomposition. The match head also contains some sulphur. Sulphur acts as a fuel. When Sulphur, oxygen and heat come together, fire is produced.
Hence a matchstick burns on rubbing it on the side of the matchbox.

Note: Another type of matchstick is “strike anywhere” matches. In these matches, the phosphorus component is also present on the match head. “Strike anywhere” matchsticks are risky as they burn when rubbed on any surface.
To generate fire, we need three things. These include heat, fuel and oxygen. Whenever we bring together fuel, heat and oxygen, we can produce fire.