Dear Mr. Scientist,
How do strike-anywhere matches work? With regular matches you have to use the special strip to light them, but strike-anywhere ones you can (obviously) strike anywhere.
—Mile D.
In order to understand how matches work, you first need to know something about phosphorus. Just as pure carbon exists in many different forms, such as graphite or diamonds, phosphorus exists in different forms. In one form it is known as white phosphorus and it has a special property—it ignites when it comes into contact with oxygen.
Both types of matches make use of this fact to create fire. The matches also contain a mixture of sulfur, phosphate and something that will cause friction (usually glass powder). Here’s where the phosphorus comes in: In matches, the stable red phosphorus form is used and is contained in either the match head (if it’s a strike anywhere match) or the strike strip. When a match is struck, the glass powder creates a lot of friction and generates heat. This heat is able to convert a small amount of the red phosphorus into white phosphorus, which ignites when exposed to the oxygen in the air. This ignites the other ingredients in the match and you get fire.
Dear Mr. Scientist,
What exactly were alchemists thinking? How did they come by the idea that they could turn lead into gold?
—Isaac J.
While the idea of turning less valuable metals into more valuable metals sounds impossible (and it is, sort of), the alchemists of the 13th through 18th centuries had a reason to believe such a thing was possible. In nature, most metals don’t occur in their pure, lustrous form, but rather as an ore where it is bound to other elements. Lead was often used during this time and a common ore that it comes from is called galena. In addition to lead, galena also contains a fair amount of silver which can be extracted from the lead. In the eyes of the alchemists, this seemed like magic: they start off with a rock, use it to get lead, then use that lead to get silver. Making the jump to gold isn’t that much of a stretch, but unfortunately for them, they weren’t aware of what was actually going on so they spent centuries chasing after an impossible dream.
Ask Mr. Scientist is written by Michael Leitch. If you have a burning science question you want him to answer, tweet @DC_Science or email it to science@dailycardinal.com.
