Question

How does a matchstick light up?

• A. Friction heats the phosphorus when struck against a rough surface.
• B. Friction heats the wood.
• C. Scratching the bulb exposes its reactive part.
• D. Friction heats the potassium chlorate in the bulb.

Answer 1

The correct option is A

Friction heats the phosphorus when struck against a rough surface.

The striking surface is made up of sand, powdered glass and red phosphorus. When the match head is dragged along the striking surface, the sand and powdered glass cause friction and heat, which is enough to convert some of the red phosphorous to white phosphorus-a chemical so volatile that it ignites in the air. The heat also breaks down the potassium chlorate in the match head, thereby releasing oxygen that serves as fuel for the fire.