Shane Owen, age lZ, of San Francisco, California, for his question:
How does striking a match create fire?
Striking a match is a bit of chemical magic that works in three stages. There are many secrets in the business of manufacturing matches, but only two secrets to the striking operation of an average match. One is friction, the other is kindling point. Each of these factors has its own set of rules. When all the rules are figured, various chemicals can be assembled so that friction starts a series of spurts and creates a flame. In other words, the right ingredients enable one to strike a match.
If you rub a patch of skin briskly for a minute or so, it becomes warm to the touch. The rubbing, of course, is friction and throughout the world of matter, friction generates heat. How much heat it generates depends on the amount of friction applied and also upon the nature of the material. A meteor speck, plunging down at 26 miles per second generates heat from friction with the air molecules enough heat to flow and burn to ashes. In this case, the friction is so intense that it ignites the mineral chemicals in the meteor.
Other chemicals require much less heat to ignite them. These are well known to match manufacturers. They mix special brews of low kindling point chemicals that require only a little heat to ignite them. From building a campfire you know that paper, slivers of wood and solid logs have different kindling points. The paper ignites from the heat of a mere match flame. As it burns it generates enough heat to reach the kindling point of the wood slivers. As they burn they create enough heat to reach the higher kindling point of the logs.
A match is constructed to use this same principle and to reduce it down to a small chemical operation. It starts as a match sized stick of wood or paper and gets treated with at least three different chemical applications. The first adds a safety coat to the stick. The chemicals in this mixture have a high kindling point. As a rule, they stop a dead match from smouldering to embers. The next step adds the bulb to the match head. The chemicals in this mixture need only a small spark to ignite them.
Then a dab of trigger sharp chemicals is added to the tip. This mixture has a very very low kindling point. The friction from striking it on a rough surface generates enough heat to ignite the match tip. This spark creates enough heat to ignite the bulbous head which bursts into flame.
The match is a very wonderful invention and most of the time it performs its duties on schedule. But the flame it creates is fire and any little fire in the world can burst out of control. The manufacturers do their very best to make matches safe but they cannot enforce safety rules on human beings. That job is up to us, which is why we always check to see that a match is properly doused and to make doubly sure outdoors, we break every dead match stick in half.