Napalm

I was told that it is possible to create a substance like napalm by combining styrofoam and gasoline and mixing until sticky…is this true? A friend of mine said that he made it sucessfully, but was what he saw just the gasoline burning? It doesn’t seem believable that these two household items could make something so dangerous…any chemists out there who know their stuff??
thanks everyone
-caitlin

Sure, it’s possible. Actual napalm is nothing but gasoline mixed with a gelling agent. It’s also been called “jellied gasoline”.

Loosely speaking your frined is correct. Although the original napalm was made from aluminum soap powder of naphthene and palmitate (hence napalm). Today those ingredients aren’t used but the resulting concoction is still called napalm. Now polystyrene (styrofoam), benzene and gasoline are the primary components.

Napalm is pretty much just jellied gasoline and is actually less flammable than gasoline. The whole point for making the stuff in the first place was to come up with something that burned more slowly than gasoline alone and would stick to its target. This allows for a greater chance of starting a fire.

You might be amazed at the nastiness people can concoct from items found even in a regular supermarket. Remember that Timothy McVeigh made the bomb that blew up the federal building in Oklahoma City from fertilizer and gasoline.

It can be as simple as that…kind of scary. One can only hope that most types who see the need to produce such things in their backyard for no good purpose (what good purpose could there be?) will blow themselves up in the process.

How did McVeigh contain the fertilizer and if it’s not too dangerous to talk about, how did the whole thing work (as a bomb). I don’t think I’ve ever seen a detailed description of what he did to concoct this deadly thing.

astro:

I do not know the details or the proper ratios for mixing such a thing as Tim McVeigh’s bomb.

What I do know and I think is safe to say is you need oxygen to burn things. Gasoline is flammable but only in the presence of oxygen (there may be other catalysts(?) as well but oxygen is certainly most easily come by). So, even if you have a big contianer of gasoline it won’t blow-up very well. Ever seen a pool of gas burn? It doesn’t blow up but just burns at the surface where it can get some oxygen.

Enter fertilizer. It essentially contains a great deal of oxygen in its makeup. Stir it up with some gasoline and ignite and now all (or at least most) of the gasoline can burn pretty much all at once.

BOOM

Was it gasoline? The explosive used is usually called ANFO: Ammonium Nitrate and Fuel Oil. Fuel oil usually meaning diesel.

Whack-a-mole, the ammonium nitrate is an oxidiser, not a catalyst. NH[sub]4[/sub]NO3[sub]3[/sub], plenty of oxygen as you point out.

astro (and mole), it’s a high explosive, not a low explosive. You could set ANFO on fire with a match and it wouldn’t do anything but burn. Some for TNT, nitroglycerin (in some situations) and a host of other high explosives.

However, when you send a shock wave through it, it detonates. Deflagration, which is fire as we know it, is pretty slow; detonation, on the other hand, is comparatively instantaneous. It’s not burning.

The bomb, and most bombs, was set off with a detonator of some kind. I don’t know the specifics of McVeigh’s, but blasting caps are a common method. A blasting cap is a small explosive charge that can set off a larger charge. By themselves they’re just strong enough to break open a concrete block or blow off your hand.

In strip mining, a common legal use of ANFO, they drill a hole, lower a chunk of a solid high explosive with a blasting cap to the bottom, then fill the hole with ANFO. A field of these holes is then set off in a carefully timed series and the rock is shattered into small enough chunks that it can be picked up and carted off by trucks and earthmoving equipment. ANFO is used for mining for the same reason McVeigh probably used it: it’s cheap; it’s safe (in mining, a truck holds tanks of AN and FO and combines them right before pumping it into the hole); it’s easy; and it packs a good wallop.

I forgot to mention: because of the high vs. low explosive thing, confinement isn’t necessary to create a big boom. An open bathtub full of ANFO detonated would have the same result as a bathtub-sized steel drum of ANFO.

You know…I actually did originally type ‘oil’ in my post but that didn’t seem right so I changed it to gasoline. It’s been awhile since I read about that stuff and ‘fuel oil’ never crossed my mind.

Thanks for the details!

I’m sorry, I know people can find this information practically everywhere online with a few seconds looking, but I am hesitant to inform someone on how to make explosives when their first post (and only, btw) is related to explosives.

Only imho.