If you've ever spent much time in American farm country, then you've probably noticed that there's a strong tradition there of coating barns and outbuildings with red paint. Why?

Because nuclear fusion.

Okay, the actual answer is simply because red paint has long been a cheap color to buy. But, explains Google engineer Yonatan Zunger, there is some really interesting physics lurking in the background of that price point.

What makes a cheap pigment? Obviously, that it’s plentiful. The red pigment that makes cheap paint is red ochre, which is just iron and oxygen. These are incredibly plentiful: the Earth’s crust is 6% iron and 30% oxygen. Oxygen is plentiful and affects the color of compounds it’s in by shaping them, but the real color is determined by the d-electrons of whatever attaches to it: red from iron, blues and greens from copper, a beautiful deep blue from cobalt, and so on. So if we know that good pigments will all come from elements in that big d-block in the middle, the real question is, why is one of these elements, iron, so much more common than all of the others? Why isn’t our world made mostly of, say, copper, or vanadium?

The answer, again, is nuclear fusion.

You can read the full story on Zunger's Google+ page. In my experience, white is another really common barn color, due to the fact that whitewash — a paint made from calcium hydroxide and chalk (which is also calcium) — is way cheap, as well. Calcium is also one of the most abundant elements in the Earth's crust ... clocking in at number 5, right under iron in the top 10. I'm sure there's some different science that accounts for the high concentrations of calcium on our planet, but the same principal applies. Cheap paint is paint made with abundant (and easily accessible) elements. And abundant elements happen because of physics.

The answer lies in another question. How can PVC — polyvinyl chloride, a commonly used type of plastic — be the stuff that makes tough, rigid sewer pipes and, simultaneously, be the stuff that makes floppy vinyl signs and cheap Goth pants?

"PVC is hard stuff. But if you put in a lot of plasticizer, you can get it to be soft," explains John Pojman, a chemistry professor at Louisiana State University. At a molecular level, PVC is a dense thing. Imagine a slinky in its stiff, compressed state. The plasticizers are chemical compounds derived from coal tar. Mix them with PVC and the small molecules of plasticizer shove their in between the densely packed PVC molecules. Imagine stretching the slinky out so that its coils are now wobbly. Same thing happens here. The more plasticizer you add, the less rigid the PVC.

And it's the plasticizers that produce that smell — the one we associate with the vinyl interior of a new car.

Ammonium nitrate is the chemical that makes these dramatic displays possible. But creating an explosion isn't as simple as just having a pile of ammonium nitrate — let alone a pile of fertilizer — sitting around. We've come to think of this as pretty volatile stuff. But, according to chemist Jimmie Oxley, ammonium nitrate is a lot less dangerous than you might guess. Despite a history of high-profile explosions, like the one that happened last night, ammonium nitrate isn't considered to be that big of a danger. In fact, Oxley called it a "marginal explosive" — a chemical that is mostly safe, but can become dangerous when the conditions are just right.

Oxley studies energetic materials at the University of Rhode Island. You could say that she studies stuff that explodes, but it actually goes a lot further than that. Energetic materials aren't just explosives. The classification includes anything that produces heat as it decomposes. That includes ammonium nitrate, but it also includes your compost pile.

"If you keep a compost heap you might have seen it steaming in the winter sometimes," Oxley said. "And it can even catch on fire. That's because biorganisms break down the compost and release heat. Sometimes, that process releases enough heat that it causes the whole pile to catch."

When it comes to energetic materials, the thing you really want to avoid is a runaway reaction, when a substance starts producing enough heat, on its own, to catch itself on fire and then keep that fire going.

But, amazingly, even that isn't enough to ensure that ammonium nitrate will explode, Oxley said. A couple of years ago, she put together a list of ammonium nitrate accidents that had happened around the world — usually in factories, or during shipping. There are 24 cases on the list that involved fire. Of those, in only 11 cases did the event go from fire to detonation.

In fact, since the 1950s, ammonium nitrate-based explosives have basically supplanted the older dynamite explosives used in mining and other industries, precisely because they are so much safer and harder to detonate. Ammonium nitrate isn't even classed as an explosive, Oxley said.

"It's very difficult to get it to detonate at a reasonable scale," she said. "You can toss 50 pounds of it in the back of your car and it will do nothing. With something like dynamite even a gram or two is highly explosive."

But, obviously, ammonium nitrate does explode sometimes. So what makes those circumstances different?

The most important factor is how much ammonium nitrate you have. Fifty pounds ain't nothing. But a couple hundred tons of the stuff is a different story. If that huge amount of ammonium nitrate also catches on fire ... then you have a problem.

As it burns, ammonium nitrate goes through chemical changes that lead to the production of oxygen. And what does a fire need to keep going and get bigger? Why, oxygen.

The largest industrial accident in the United States happened in 1947, off the coast of Texas City, Texas, when two shipping vessels full of ammonium nitrate exploded. Six hundred people were killed. The explosion might not have happened had the captain of one of the two ships adopted a different tactic for fire-fighting. When he realized his hold was in flames, Oxley said, he had a choice — drown the fire or smother it. The captain opted for smothering it, sealing the hold and trying to starve the fire of oxygen. But the pyre of burning ammonium nitrate was producing its own oxygen. Instead of putting out the flames, the act of sealing the hold allowed the fire to burn bigger and longer without inturruption.

Contrary to some explanations, you don't need a physical jolt to make a great big pile of burning ammonium nitrate explode. The fire alone will do just fine, Oxley said. That's because, depending on how the ammonium nitrate is packed together, the heat can create a sealed plug, trapping hot gases.

Think of a cigarette, she said. When you light it, most of the gas flows away from the cigarette. But some doesn't. That stuff that hangs around helps to pre-warm the parts of the cigarette that haven't already caught fire. That same basic process can happen with a pile of burning ammonium nitrate, only, in that situation, the pre-warmed chemical can end up fusing together. The space behind the plug keeps on being heated and gases form. Hot gas expands, but, behind the plug, it has nowhere to go. Eventually, the gas will break through the seal and the force of that will trigger an explosion.

• Image: Ammonium Nitrate, a Creative Commons Attribution (2.0) image from philliecasablanca's photostream
• Image: Ammonium Nitrate, a Creative Commons Attribution Share-Alike (2.0) image from mgspiller's photostream

This is his business card.

It's a microscope image of the world's tiniest periodic table, which Poliakoff's friends inscribed on a strand of his own hair as a birthday gift in 2010. The hair, which Poliakoff keeps in a glass vial, has earned him a spot in The Guinness Book of World Records.

Not all snowflakes are unique in their shape. There's one fact for you.

And here's another: The shape of snowflakes — whether individually distinct or mass-production common — is determined by chemistry. Specifically, the shape is a function of the temperatures and meteorological conditions the snowflakes are exposed to as they form and the way those factors affect the growth of ice crystals.

This short video from Bytesize Science will give you a nice overview of snowflake production and will help you understand why some snowflakes are unique, and why others aren't.

True Chemistree (imgur.com) ]]> http://boingboing.net/2012/12/15/chemis-tree.html/feed 3 http://boingboing.net/2012/12/03/molecules-with-silly-names.html http://boingboing.net/2012/12/03/molecules-with-silly-names.html#comments Mon, 03 Dec 2012 16:39:57 +0000 Maggie Koerth-Baker http://boingboing.net/?p=197869

Meet moronic acid. It's special.

Seriously.

Found in mistletoe and the Chinese sumac, this chemical could be one of the reasons those plants have long been associated with herbal medicine. Scientists studying the anti-viral properties of moronic acid have found it to be effective against HIV and herpes. The HIV work is particularly important, because moronic acid seems to target a different receptor on the virus than other drugs — which means it could be effective against HIV strains that have developed a resistance to existing medication. It'll still be a while before this research translates into a commercial product (if it does at all). But moronic acid is, at least, doing well enough to have made it into Phase II clinical trials — which means that smaller studies on humans have shown that it's generally safe. The Phase II trials, usually done with groups of 100 to 300 people, will help scientists understand whether it's as effective in the human body as it seems to be in the lab.

Looking for more molecules with silly names? Chemist Paul May has a whole list of these things — many of them hilariously immature. List includes arsole, cummingtonite, and fucitol.

Via the Daily Molecule and Deb Blum

University of Kentucky chemistry professors John P. Selegue and F. James Holler are collecting comic book references to chemical elements. On their Periodic Table of Comic Books site, you can click through the standard periodic table to see pages from comic books that mention specific elements. The samples seem to be weighted pretty heavily to classic, Golden and Silver Age stuff — there's a lot of 1940s Wonder Woman and miscellaneous anthology series from the 1960s.

They don't have all the elements accounted for yet. In particular, the lanthanides and actinides — aka, those two rows at the bottom where everything ends in "ium" — are lacking comic book shout-outs. Maybe you can help!

Visit the Periodic Table of Comic Books

Paige the border collie can load the washing machine, pick up trash, and make toaster waffles (although you probably don't want to eat them afterwards).

And, with the help of her colleague Dexter — and their owner/trainer, who is also a chemist — Paige can even teach chemistry.

Here, Paige and Dexter serve as models for a discussion about chemical bonds — the forces that attract one atom to another and form the basis of all the chemicals that make up our world.

Via Matthew Hartings

Yesterday, Cory posted a vintage ad for boys' hats and accessories, which included a small selection of ties made from something called "Aralac". I didn't think much of it, until I noticed J. Brad Hicks' comment pointing out that Aralac was a synthetic wool made from cheese. Which was not a joke.

Seriously. It'll make more sense once you understand how the stuff was actually made.

Think about it this way: Wool (the actual kind, that comes from sheep) is a protein. So is casein, which is found in milk. Making Aralac is basically about getting the protein casein to behave like the protein wool. In 1937, Time magazine described how the process worked:

Having practically the same chemical composition as wool, it is made by mixing acid with skim milk. This extracts the casein, which looks like pot cheese. Evaporated to crystals, it is pulverized and dissolved into a molasses consistency, then forced through spinnerets like macaroni, passed through a hardening chemical bath, cut into fibres of any desired length. From 100 pounds of skim milk come 3.7 pounds of casein which converts to the same weight of lanital. [Aralac was also called Lanital.]

Casein isn't cheese, as J. Brad Hicks described it. Instead, it's the stuff that makes cheese happen. If milk is the liquid and cheese the solid, casein is the stuff that facilitates the transition — the casein in milk clumps together and solidifies into cheese.

So, in a way, Aralac really was cloth made from cheese. During World War II, when wool was scarce, it made a lot of sense to buy Aralac — which was significantly cheaper and easier to get a hold of.

Why don't we wear Aralac today? Couple reasons. First off, it wasn't a particularly strong fiber. According the Powerhouse Museum in Sydney, Australia, Aralac fibers were only about 10% as strong as natural wool, so the stuff was usually mixed in a wool-Aralac blend to improve durability. And, despite assurances to the contrary in that 1937 Time story I quoted above, Smithsonian says Aralac was a royal pain to successfully dye.

It's also worth noting that Aralac isn't totally gone. In fact, there's a German company trying to market QMilch — a fabric made from milk that isn't deemed high enough quality to be sold as food. It's apparently more like silk than wool.

• The Time magazine story is behind a paywall, but you can read a 1944 Life magazine piece on Aralac for free at Google Books.
• Smithsonian on H. Irving Crane, inventor of Aralac
• The Powerhouse Museum on Aralac and other synthetic fibers
• Read a brochure on Aralac from the 1950s

Special thanks to J. Brad Hicks and the Knitty Professors blog

Sometime in the late 1980s or early 1990s, my mom bought me a chemistry set. I was in grade school, but I remember thinking it was pretty cool. I also remember being slightly disappointed (particularly after being told that I could only play with it in the garage) that there was nothing in there that could actually blow up.

Many of us are nostalgic for the lost golden era of certifiably dangerous children's chemistry sets. Even if we weren't alive when that era occurred, we're still, sort of, vicariously nostalgic. At the BBC, Alex Hudson has a story about what was really in those misty colored chemistry sets that have lodged themselves into our cultural memory. Along the way, we learn that their demise was only partly to do with unfounded safety fears—some of the fears were founded, for instance, and in other cases, money and seemingly unrelated legal issues got in the way of fun.

By the 1920s and 30s children had access to substances which would raise eyebrows in today's more safety-conscious times. There were toxic ingredients in pesticides, as well as chemicals now used in bombs or considered likely to increase the risk of cancer. And most parents will not need to be told of the dangers of the sodium cyanide found in the interwar kits or the uranium dust present in the "nuclear" kits of the 1950s.

Most will know cyanide as a deadly poison, but one of its main applications is in gold mining. It can make gold dissolve into water.

...Used often to test the presence of starch, the iodine solution once seen in kits is now regulated as a list I chemical in the US because of its use in the manufacture of methamphetamine. It can also be lethal if more than 2g of pure iodine is consumed.

Read the rest of this story at the BBC

To celebrate the premiere of Breaking Bad's Fifth Season this week, my fellow trufan Miles O'Brien and I dug into the show's vaults to explore the top 10 chemistry moments in Breaking Bad, from seasons One through Four. Only, there was so much awesome science, we had to choose 11 top chemistry moments, instead.

Also, check out our excellent adventure: air-dropping in to a random Breaking Bad fan's premiere party in the show's hometown of Albuquerque, NM.

[Video Link]. More Boing Boing coverage of Breaking Bad here.

Assembled by Joe Sabia (Twitter: @joesabia, web: joesabia.co). Check out his CDZA project on YouTube, too. Thanks, Joe!]]> http://boingboing.net/2012/07/19/top-11-chemistry-moments-in-br.html/feed 50 http://boingboing.net/2012/06/14/film-soaked-in-hydrochloric-ac.html http://boingboing.net/2012/06/14/film-soaked-in-hydrochloric-ac.html#comments Thu, 14 Jun 2012 19:22:36 +0000 Maggie Koerth-Baker http://boingboing.net/?p=166376

MattAttackPro is a chemistry and physics teacher in South Carolina. This is what happened when he dropped a roll of unused camera film into a container of hydrochloric acid.

What you're seeing is the plastic backing separating from the "film" from which film takes its name—a coating of multiple layers of light-sensitive salts suspended in gelatin. Yes, film is like a jello salad. And it makes for a beautiful photograph.

See the photo on Instagram

Used to paralyze patients so that doctors can more easily put insert a breathing tube, the drug can kill very easily if the person who gets a dose of it doesn't have access to things like respirators, or a medical team. And when somebody is killed by "sux", the death can look conveniently like a simple heart attack. More importantly, writes professional chemist and anonymous science blogger Dr. Rubidium, for many years, there was no way to test for sux in a dead person's bloodstream.

Since the early 1950s, sux has been used in a clinical setting mainly by anesthesiologists. It’s a mystery when it was first used in a homicide, but the first high-profile killings came in the 1966 and 1967. This salacious tale of murder involves anesthesiologist Dr. Carl Coppolino, his mistress, his mistress’ husband dying suddenly in ’66, Coppolino’s wife dying suddenly in ’67, a quick remarriage by Dr. Coppolino (not to that mistress), two trials in different states leading to different verdicts.

Coppolino’s first trial in New Jersey involved a shaky witness (that jilted mistress) and a tricky toxicology problem. ...

Back in the mid-to-late sixties, sux was likely considered a “perfect poison” as no tried-and-true method for detecting it in tissues was developed until the 1980s. Previous analysis had holes – including the analysis presented in both of Coppolino’s trials. It wasn’t sux that was detected, but the metabolites succinic acid and choline.

You can read the rest of Dr. Rubidium's post at The Journal of Are You Fucking Kidding.

Her post is part of a bigger series, though. If you dig weird, toxic chemicals, you should check out the "My Favorite Toxic Chemical" blog carnival—a collection of horrifying and wondrous posts about poisons.

Toxic Chemical Carnival: Day 1
Toxic Chemical Carnival: Day 2
Toxic Chemical Carnival: Day 3
Toxic Chemical Carnival: Day 4
Toxic Chemical Carnival: Day 5

A great short video from a CalTech gas-sensing lab explains the science of gas-detection and analysis.

The Electronic Nose: Sniffing Out the Dangerous Stuff to Keep Our Noses Safe (Thanks, Scanadu) ]]> http://boingboing.net/2012/05/22/how-electronic-smell-detection.html/feed 6 http://boingboing.net/2012/05/15/t-shirt-tribute-to-the-time-ho.html http://boingboing.net/2012/05/15/t-shirt-tribute-to-the-time-ho.html#comments Tue, 15 May 2012 14:32:37 +0000 Maggie Koerth-Baker http://boingboing.net/?p=160831

We can argue for days over which field of science is the booziest (I used to say archaeology, but have since switched my vote to ocean science). But we can all agree on the adorableness of this Threadless T-shirt, which provides a quick introduction to molecular bonding. Will they feel as bonded in the morning? It's hard to say.

All this week, The Chicago Tribune is posting a multi-part investigative report about the fire-retardant chemicals that turn up in everything from the foam in our couch cushions, to the plastic casings on our television sets. Turns out, research shows these chemicals don't actually prevent fire deaths and injuries. Worse, research does show that these chemicals are dangerous to human health—especially in the quantities to which we are exposed. Dose makes the poison, but we're not talking about small doses here. As the Tribune so succinctly puts it: This isn't something where we measure exposure in parts per million, it's measured in pounds.

The Tribune has also done a very good job of documenting both the existence and history of a pattern of corporate lies and manipulation that has made sure these chemicals remained a mandated part of our lives even as science shows they aren't helping us.

The lies are infuriating, but the history part is particularly fascinating. After all, it's easy to understand why chemical companies would lie and manipulate politics in order to maintain a lucrative market for their products. But why does that market exist, to begin with? Behind the scenes, our continued exposure to these chemicals comes down to two key issues: One poorly designed product safety test that encouraged heavy use of flame-retardants in foam instead of small doses of safer chemicals in fabric, and a 1970s-era attempt to deflect negative press away from cigarettes.

The problem facing cigarette manufacturers decades ago involved tragic deaths and bad publicity, but it had nothing to do with cancer. It had to do with house fires.

Smoldering cigarettes were sparking fires and killing people. And tobacco executives didn't care for one obvious solution: create a "fire-safe" cigarette, one less likely to start a blaze. The industry insisted it couldn't make a fire-safe cigarette that would still appeal to smokers and instead promoted flame retardant furniture — shifting attention to the couches and chairs that were going up in flames.

But executives realized they lacked credibility, especially when burn victims and firefighters were pushing for changes to cigarettes. So Big Tobacco launched an aggressive and cunning campaign to "neutralize" firefighting organizations and persuade these far more trusted groups to adopt tobacco's cause as their own. The industry poured millions of dollars into the effort, doling out grants to fire groups and hiring consultants to court them.

Playing With Fire: The entire four-part series updated all this week.

So far, parts 1 and 2 have been published.

"We can fabricate these reactionware vessels using a 3D printer in a relatively short time. Even the most complicated vessels we've built have only take a few hours.

"By making the vessel itself part of the reaction process, the distinction between the reactor and the reaction becomes very hazy. It's a new way for chemists to think, and it gives us very specific control over reactions because we can continually refine the design of our vessels as required.

"For example, our initial reactionware designs allowed us to synthesize three previously unreported compounds and dictate the outcome of a fourth reaction solely by altering the chemical composition of the reactor."

...Prof Cronin added: "3D printers are becoming increasingly common and affordable. It's entirely possible that, in the future, we could see chemical engineering technology which is prohibitively expensive today filter down to laboratories and small commercial enterprises.

"Even more importantly, we could use 3D printers to revolutionise access to health care in the developing world, allowing diagnosis and treatment to happen in a much more efficient and economical way than is possible now.

"We could even see 3D printers reach into homes and become fabricators of domestic items, including medications. Perhaps with the introduction of carefully-controlled software 'apps', similar to the ones available from Apple, we could see consumers have access to a personal drug designer they could use at home to create the medication they need."

'DIY drugstores' in development by Glasgow University researchers ]]> http://boingboing.net/2012/04/17/printing-pharmaceuticals-w.html/feed 22 http://boingboing.net/2012/04/13/what-is-used-book-smell.html http://boingboing.net/2012/04/13/what-is-used-book-smell.html#comments Fri, 13 Apr 2012 21:52:09 +0000 Cory Doctorow http://boingboing.net/?p=154444

In this short video, Richard from ABEbooks describes the distinctive smell of old books ("a combination of grassy notes with a tang of acids and a hint of vanilla, with an underlying mustiness") caused by hundreds of volatile compounds released during the slow oxidization of the paper, glues and inks.

Why Do Old Books Smell? (via Neatorama) ]]> http://boingboing.net/2012/04/13/what-is-used-book-smell.html/feed 21