The artificial sweetener Splenda was discovered
when a chemistry grad student misunderstood his advisor's instructions to "test" a compound and tasted it, instead. (This piece at Scientific American focuses on how the brain responds to, and is changed by, sweeteners.) — Maggie
How the ancient Romans created color-changing glass goblets
that shifted colors based on what you put in them. — Maggie
At Popular Mechanics, an analytical chemist uses clues from Breaking Bad
to explain both the real science behind Walter White's meth formula, and the key flaw that either means the show's writers are taking a little artistic license or
Walter is even more of a chemistry genius than anybody thought. — Maggie
Ancient Roman cosmetics were notoriously poisonous — despite the fact that it was already a well-known toxin
, folks slathered their faces in white lead and dabbed red lead rouge on their cheeks. You wouldn't drop dead from a single application. The problem built up over time, as more and more and more of the stuff was applied (and absorbed) by your body. And that's still true today. In a new column for The New York Times — all about chemicals and your environment — Deb Blum writes about the lead (and aluminum and cadmium and all sorts of of other metals) that contaminates modern lipstick
. The doses are low, much lower than Roman times. But the reapplications are many. Lipstick wearers touch up their color as often as 20 times in a single day. — Maggie
The blue meth made by Walter White is bluer than any meth that could actually exist in real life — and other interesting things that you learn while talking to Breaking Bad's scientific advisor
, University of Oklahoma chemistry professor Donna Nelson. — Maggie
The Earth is about 4.5 billion years old.
Actual dirt — that is to say, like the stuff in your backyard, not rocks that were once
dirt — probably dates to about 2 million years ago
. Dirt is young! (Relatively speaking.) — Maggie
The diving gear might be a bit of a tip-off, but this fellow isn't sat on a log, fishing. In fact, he's 90ft underwater, posing above the murk that forms where fresh and salt water meet. Photographer Anatoly Beloshchin captured these and many other stunning pictures in and around the depths. [Daily Mail]
An actual chemist looks at claims made about "toxic foods" in a recent Buzzfeed linkbait post and calmly explains
why the whole thing is ridiculous. Of the 8 foods (actually, mostly food additives) mentioned, one is hardly used anymore, another was withdrawn from the market two years ago, two only sound scary if you failed chemistry, and four have had their risks vastly overstated. It's the sort of situation where some studies show a risk, some studies don't, and there's good reasons to think the risk — if it exists — isn't that big, to begin with. — Maggie
There is nothing wrong with adding ice to scotch,
writes Kevin Liu at Serious Eats. In fact, a little water can change the flavor profile of the drink for the better. What's more, chilling your scotch won't dampen down the aroma. A chilled drink won't be flinging off scent molecules left and right, but it will warm up enough from your hot breath to get the chemistry of scent where it needs to go — and to give you the flavor experience you want. — Maggie
It starts with lignin — a compound that makes up the cell walls of plants. Turns out, it's also closely related (chemical-structure-wise) to vanillin, the stuff that makes vanilla smell so vanilla-y. Given that books are full of the broken-down cell walls of trees, a big part of what we think of as "old book smell" is actually a scent similar to vanilla. — Maggie
Guidebook for the Scientific Traveler
, published in 2010 and written by Duane Nickel, promises to be a tour guide to chemistry and physics points of interest all across the United States. (Thanks Tim Heffernan!) — Maggie
Science Buddies has an interesting, springtime-themed experiment in the chemistry of color that you can do at home, using plants you've gathered from your yard or a park. It looks like a great activity for curious folks of all ages
. — Maggie
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.
Image: Red Nebraska Barn, a Creative Commons Attribution No-Derivative-Works (2.0) image from 50779843@N03's photostream
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.
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