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 Lupo 11-27-2009 02:38 AM

Hey,
A friend of mine and I are doing a project for our 11th grade Chemistry class. Everyone in the class has to take a chemical reaction in everyday life and do a project on it. My friend and I chose to do smokeless powder. I need some assistance though. To do this project we need the chemical equation of what happens when the firearm goes off. The equation must go something like this

spark from primer + gunpowder = the gas it gives off.

Now I need to take that and put in chemical equation form with all the elements, coefficients, and subscripts. PLEASE, any help would be grateful, even just a general equation it doesnt have to be for a particular powder.

Or, if anyone knows a place i could call up to get some answers and information please do not hesitate who i should contact.
Thank you.

 jpattersonnh 11-27-2009 02:40 PM

http://www.fas.org/man/dod-101/sys/land/docs/ordtech.pdf
Powley Computer Notes
http://www.arl.army.mil/arlreports/2004/ARL-TR-3301.pdf

These may help. You may also want to check your library for books on pyrotechnics and cartridge development.

Your equation should be Primer ignition, Powder ignition, pressure created/ expanding gases.

 1hole 11-28-2009 12:28 AM

"spark from primer + gunpowder = the gas it gives off."

Uncontained smokeless powder is NOT and explosive but it does burn fast and gives off large qualinties of gas. Unless your school lab has a specromerter, keep the question simple. Perhaps limited to the actual volume of gas produced, as Mr. Patterson suggests.

You could then use the gas laws of physics (Boyles Law) to compute the (approximate) pressure that would be produced inside the small volume of a brass cartridge case, which you would also have to measure. Do that with water, in CC, converted to cubic inches if you wanted to push it. You won't be totally accurate but who cares, it will still sound good for a school project! :D

SO ... you do NOT want to use a large quanity of powder, or your principle will panic. Use perhaps no more than a level tea spoon full, uncontained except for a large bowl or something like that for a burn chamber, and perhaps use a hot wire for ignition. I suggest you try to capture the gas produced in something like a large (deflated) balloon. Measure the resulting volume and do the computations. If you don't know how to do the volume vs. pressure calculation, contact your schools physics teacher, he will likely be glad to show you how to do it.

Good luck!

 Lupo 11-28-2009 01:13 AM

All this information is very helpful, but I am wondering if anyone can give me a generic equation. I am really needing assistance on this project. I am not looking for a particular load or anything. Please I need this info by around tuesday to complete the project.

 N.D. 11-29-2009 11:02 PM

Sorry this is above my pay grade "but"! . . jpattershonn really did give you a good point in the right direction for research material.
I once many YRS ago had a table that listed the expansion rates of most known explosives (substances that have been used by man to blow things up) this list started w/ Black powder and went all the way to the substance just before a Nuke then stopped.
I know this isn't much help to you but I do hope it was some help & I wish you good luck with your project.

 1hole 11-29-2009 11:31 PM

"I am wondering if anyone can give me a generic equation."

No "load data" would apply to an unconfined burn. What equation are you seeking, what do you want it to show or compute?

 DrJason 11-29-2009 11:33 PM

What ever happened to going to the library and looking at books for information?

 Lupo 11-29-2009 11:43 PM

How a bullet goes off is the equation i want.
The primer + the powder = the gas

 mrm14 11-29-2009 11:56 PM

A gas chromatograph would really help to determine the exact chemical compound of the smokless powder and primer to write a more exact equation. Does your shool have one? Or; Do you have access to one?

 1hole 11-30-2009 01:21 PM

What I want = "The primer + the powder = the gas"

Sorry, there is no such formula.

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