— FEATURED —
— FOLLOW US —
— POLICIES —
Except where indicated, Boing Boing is licensed under a Creative Commons License permitting non-commercial sharing with attribution
— FONTS —
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.
Image: 365:37 - Mar 29 - that new car smell, a Creative Commons Attribution Non-Commercial No-Derivative-Works (2.0) image from waldengirl's photostream
Fertilizer can explode*. We all know that. It was a key ingredient in the bomb that destroyed Oklahoma City's Alfred P. Murrah Federal Building in 1995. Last night, a factory full of the stuff went up with enough force that United States Geological Survey seismographs registered it as a magnitude 2.1 earthquake.
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.
Read the rest
Tonight, I got to meet Martyn Poliakoff — the fabulously frizzy-haired University of Nottingham chemist who you might recognize from a series of awesome videos about the periodic table that Xeni first blogged about back in 2008.
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.
Meet moronic acid. It's special.
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.