Explosives
sporte | November 29, 2008It's a long, long, weekend; perfect for going outside and doing a few loud, messy experiments. Cooking-intensive holidays always remind me how much fun it is to do a bit of chemistry, especially when it comes to food.
If you watched the video that I posted on Thanksgiving, you've probably been itching to try one of these experiments yourself.
Some chemistry experiments are better in the spring, especially if you're using peeps, but experiments with candy and soda pop can happen anytime.
If you'd like to give these sorts of experiments a try, the Disgruntled Chemist posted a truly…
moleculeoftheday | August 27, 2008Potassium chlorate, KClO3, is quite oxygen-dense and a potent oxidant. It is used in what we called "whippersnappers" and the suppliers called "Pop-Pops" as kids, along with silver fulminate. There is a singular irony in that the wimpiest firework, the one we could buy even in my solidly blue no-fireworks mommy state, contains two components of some dangerous explosives. But we're talking micro- to milligrams, so don't get any ideas.
Oh, who am I kidding, you just want to see it destroy a gummi bear:
sporte | August 22, 2008The Periodic Table of Videos from the University of Nottingham has 118 short YouTube clips about the elements. Wired Campus recommended the Sodium clip (below). I liked it, too. It's not quite as funny as Mentos in Diet Coke, and but it's still cute and the narrator has a haircut like Gene Wilder in Young Frankenstein.
H/T: Wired Campus.
moleculeoftheday | May 15, 2008Hexamine is a nitrogenous analogue of adamantane.
The coolest thing about it is the exceptionally stable adamantyl-type system assembles on its own if you just mix ammonia and formaldehyde gas. It's got loads of uses, from little fuel tabs for stoves, to a component of explosive mixtures, to deodorant in China (anyone care to elaborate?)
moleculeoftheday | April 2, 2008Benzoyl peroxide is funny. As a commenter mentioned yesterday, it's used in skin care.
It's a potent oxidizer (and will quickly do a number on reducing agents like hydroquinone, which is the reason for the warning mentioned). Potent enough that it's an explosive. At 2.5-10% concentration, however, it's used in creams as an antimicrobial agent in the treatment of acne.
moleculeoftheday | March 5, 2008As a commenter surmised in my entry on phosphine, I really like Breaking Bad. The main character is a chemist, and the writers have done a good job of working a lot of chemical tidbits into the mix (even ones not about methamphetamine, which drives much of the plot).
Now through Friday: molecules from Breaking Bad that aren't methamphetamine (or even related to it) (spoilers inside).
With pressure or friction, it will explosively decompose into nitrogen, carbon monoxide, and mercury metal.
Mercury fulminate made an appearance in last Sunday's episode. He takes a giant sack of the stuff into…
moleculeoftheday | November 30, 2007A lot of science-fiction writers have spent a lot of time and energy hypothesizing silicon-based life. This isn't completely insane - if you go down a column of the periodic table, stuff tends to be the same. Fluorine, chlorine, bromine, and iodine all share properties, and so do carbon, silicon, germanium, tin, and lead. Some properties.
Silane, SiH4, is the silicon analogue of methane, CH4. Not nearly the same, though - it flames in air and burns to become sand - SiO2, which is just the silicon analogue of CO2, which is a gas!
An element's chemistry is defined by its interactions with other…
moleculeoftheday | November 14, 2007Ethylene glycol dinitrate is simply the dinitrate ester of ethylene glycol - putting glycol under the same reaction conditions that yield the primitive nitro explosives, like nitroglycerin or TNT, yields this compound. Why's it important? It has a decent vapor pressure.
The volatility allows the compound to be detected by dogs and those machines they use at the airport. While it's explosive, it has nowhere near the destructive power of what it's mixed with. Manufacturers add it (and similar compounds, lately) to their explosives as a so-called "taggant." It doesn't affect performance, but it…
moleculeoftheday | October 8, 2007Picric acid is a simple enough organic acid - its nitro groups withdraw electrons, making it a pretty strong acid for a phenol. However, it's got a slightly darker side: it's to TNT what phenol is to toluene. Those nitroes come with a price.
Picric acid is funny; like raney nickel, it's much more benign under water. For this reason, it's sold that way. Dry picric acid or its metal salts can be quite nasty. From time to time you hear about an old container of the stuff being discovered and the bomb squad coming out.
moleculeoftheday | August 1, 2007I love old bottles of chemicals, and I've spent many a diverting hour perusing the shelves of old university faculty members' labs. Bottles used to come in pounds (or giant "ONE MOLE" sizes). Faded typewritten text, "For medical, pharmaceutical compounding, or research use" labels, yellowed paper - Korean war-era bottles are about as romantic as bottles of chemicals get.
When it's old ether, though, I get away and make a note to warn someone (and not come back anytime soon).
Ethers - chemicals of the general formula R-O-R', can form peroxides (R-O-R'-OOR'') at the carbon adjacent to the…
moleculeoftheday | August 10, 2006I was a little uneasy about writing about this one, since I was worried someone would try and make it. The image for this entry actually went through a few iterations, first, with a detailed explanation of the mechanism. Then, I cut it down to just the stepwise formation of the dimer and trimer. Then I decided it was probably better to leave bad enough alone and just show the structure:
It seems like terrorism news, like Richard Reid's (the "shoe bomber") bombing attempt, the 7/7/05 tube bombings, and, as mentioned on Pure Pedantry, yesterday's apparent thwarted UK-US flight attack, always…