Reply #14: Well, i Am A Chemist [View All]

[ProfessorGAC]

Among other things now, but my first graduate degree is in theoretical chemistry. The answer is VERY few.

There are some flammable liquids with massive explosive force, but only a couple that would generate a supersonic shock wave. (For instance, ethylene oxide.) But, the example i gave is a very volatile, and high vapor pressure material and wouldn't be able to be contained within a plastic bottle. It requires pressurized metal containers. (Something akin to a small beer keg.)

There are of course liquid high explosives (like nitroglycerin), which would pack a huge wallop (the technical term :evilgrin:). But, handling that is limited to 20g or less, even in the manufacturing conditions, where there are experts in synthesis and handling and the conditions are as good as they can possibly be. Nitroglycerin is shock sensitive enough that it could go off in someone's carryon bag just be being jostled on the XRay machine belt!

One could make things VERY scary on a plane with a myriad of liquids that would conflagate, but not detonate. (Those are two very different chemical phenomena.) But, these would not take down a plane. Even gasoline, which is about the most volatile liquid organic that is available in everyday life, would not detonate.

The thing is, the detonation or highly rapid conflagration of an organic liquid requires extremely precise fuel air mixtures and an appropriate ignition source. Not that i recommend it, but one could put out a match by pouring a shot glass of gasoline on it. The mixture would be well above the upper explosion range of gasoline.

Also, remember that liquids, (in vast preponderance) do not burn. The vapor above the surface of the liquid is what burns. So, it's very hard to get an organic liquid, which is stable enough to haul around in a bag or in the pocket, that would burn beyond the small amount of vapor caused by the vapor pressure differential at any given temperature.

Another for instance: A 20ml bottle of gasoline won't burn if the bottle is full. That 20ml would have to be liberated as vapor into an appropriate amount of air volume, then ignited. Now, once that starts, the heat of that combustion would evaporate more of the liquid, which extends the combustion, and so on. The three key steps in all chemical reactions are Initiation, Propagation, and Termination. (The "IPT" of chemistry.) If one can't initiate, all else matters not!

Like i said, if someone had a highly flammable liquid and did initiate combustions, that would be VERY scary and dangerous on an airplane. But, it wouldn't create the sort of shock wave or overpressure that would bring down a plane.
The Professor