UCSB Science Line
Sponge Spicules Nerve Cells Galaxy Abalone Shell Nickel Succinate X-ray Lens Lupine
UCSB Science Line
Home
How it Works
Ask a Question
Search Topics
Webcasts
Our Scientists
Science Links
Contact Information
Why does gunpowder explode when lit?
Question Date: 2013-09-06
Answer 1:

It doesn't, actually. Gunpowder burns very, very quickly, on account of the fact that one of its components, potassium nitrate, supplies oxygen to the charcoal and sulfur to achieve an accelerated burn rate. This combustion produces a much larger volume of hot gas than the gunpowder itself, and if that gas is in a combined space, then it will force its way out with an explosion. However, if the gunpowder is not in a confined space, then it will just burn since the gas will simply expand into the surrounding air.


Answer 2:

Excellent question! Gunpowder is a powder mixture of very combustible (burnable) chemicals, namely sulfur, charcoal, and potassium nitrate.

When you light gunpowder on fire, the same type of chemistry is happening there as when you, for instance, burn firewood in a fireplace or light up charcoal on a barbecue grill. Burning materials release heat and hot gas at different rates depending on their properties. Since gunpowder comes in a fine powder, a lot of it is quickly burned, resulting in a lot of hot gas and heat being released at once. All this energy forces the gunpowder outward, further igniting more of it and causing the explosion that we can see.


Answer 3:

What makes gunpowder seem to "explode" is because it burns very rapidly. It seems to explode because when it is compressed in a barrel, it is packed in a very tiny space which means great pressure. So when it burns very fast, in a very confined space, the gases are built up and "explodes".



Click Here to return to the search form.

University of California, Santa Barbara Materials Research Laboratory National Science Foundation
This program is co-sponsored by the National Science Foundation and UCSB School-University Partnerships
Copyright © 2017 The Regents of the University of California,
All Rights Reserved.
UCSB Terms of Use