Note (12/2015): Hi there! I'm taking some time off here to focus on other projects for a bit. As of October 2016, those other projects include a science book series for kids titled Things That Make You Go Yuck! -- available at Barnes and Noble, Amazon and (hopefully) a bookstore near you!

Co-author Jenn Dlugos and I are also doing some extremely ridiculous things over at Drinkstorm Studios, including our award-winning webseries, Magicland.

There are also a full 100 posts right here in the archives, and feel free to drop me a line at with comments, suggestions or wacky cold fusion ideas. Cheers!

· Categories: Chemistry
What I’ve Learned:

Sublimation: it's just nature's way of cutting to the chase.
“Sublimation: It’s just nature’s way of cutting to the chase.”

The word “sublimation” can mean a number of different things. In psychology, sublimation is an emotionally-driven defense mechanism identified by Friedrich Nietzsche, and then turned by Freud into some wild-ass uncomfortable shit about your mother. Because that’s what Freud did to everything.

Sublimation can apparently also mean brainwashing someone to listen to a certain ’90s surf-ska-punk band at high volume until three in the morning, which some sadistic asshole seems to have done to our upstairs neighbor. I’d wish some sick Freudian thing on them both — but it’s the wrong way.

In scientific terms, sublimation is the process where a solid substance decides it’s not going to bother with becoming a liquid, and changes directly into a gas. Skipping the whole “melting” thing can be a real time-saver — like eating breakfast in the shower or getting dressed without underpants.

Of course, it takes a special set of circumstances for this molecular commando-ing to work. Most substances move from solid to liquid, and then liquid to gas, as the temperature rises. But at just the right combination of temperature and pressure, some compounds can be coaxed to slide straight from solid to vapor, without any of the wet stuff in between.

Which is usually not at all the way “going commando” works. So it’s all the more impressive.

Every chemical compound has something called the “triple point”, a pressure and temperature combination where it can exist in a solid, liquid and gaseous state in equilibrium. Think of it as a Zen thing — or, if you prefer, a big bowl of Neapolitan ice cream. All flavors at once, and one for all. Below this triple point, sublimation can occur. That happens at extreme conditions for most substances — but not all.

One familiar example of sublimation is often seen in science labs, haunted houses and cheesy productions of Phantom of the Opera. Namely, dry ice — which is the solid form of carbon dioxide. Instead of melting, dry ice gives off those spooky clouds of vapor that people associate with Halloween, spooky forests and black lagoons from which creatures are likely to emerge.

But even plain old water — or technically, ice — can sublimate, and at temperatures we’re familiar with. For instance, the process of freeze-drying food involves sublimation of ice crystals. So does freeze-drying’s sadder, uglier cousin, freezer burn. And glaciers and mountaintops and even comets can lose some of their ice via direct sublimation, as well.

One process that isn’t sublimation, despite the name, is (most) dye-sublimation printing. When these printers were first developed, it was thought that the dyes used literally sublimated from solid to gas — but it was later found this wasn’t the case. Still, the marketing was already in place — and you don’t say “no” to the advertising execs, so the name stuck. But in reality, only the fancier-sounding “dye sublimation heat transfer imprinting” printers are worthy of the name, and actually use sublimation.

(And just like everything in this world that needs five words to describe, they’ll cost you.)

So sublimation isn’t so strange, though it takes an odd sort of chemical shortcut to make it happen. But some days, you just don’t have time to cycle through all the phases of matter. Sublimation is just a quick way to get straight from solid to gas, without a lot of mucking about in between.

Or a lot of underpants. Like they say, sometimes science can get a little messy.

Actual Science:
BoundlessSolid to vapor process
Answers.comSublimation: chemistry’s phase transition
University of Toronto ScarboroughSublimation theory
USGSSublimation – the water cycle

Image Sources: Explain That Stuff (phase diagram), Shower Food (just what it says), Bang 2 Write (Neapolitan scoop), The Hour (foggy Phantom)

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· Categories: Chemistry, Physics
What I’ve Learned:

Absolute zero: where the temperature itself is strange and unusual.
“Absolute zero: where the temperature itself is strange and unusual.”

You may think you’ve experienced extreme cold. Maybe you accidentally swallowed a whole popsicle once. Or walked into a blizzard with your fly unzipped. Maybe you have a regular bridge game with Betty Draper, April Ludgate and Cruella de Vil.

That’s super. But none of those things compare with absolute zero.

Absolute zero is a theoretical state of matter in which the enthalpy and entropy of a gas are at their lowest possible values. This sounds complicated, but “entropy” and “enthalpy” just mean the amount of energy in the system, and the disorder of that system.

(I can never remember which is which, because the words sound too much alike.

I also mix up Mindy Kaling with Michael Keaton. Which makes reruns of The Office pretty confusing — and Beetlejuice ten times scarier.)

In more familiar terms, absolute zero would be -273.15° Celsius, or -459.67° Fahrenheit, either of which will shrink it right up inside you in a hurry. It’s also zero Kelvin, which is a lot easier to remember. On the other hand, it’s 288 Kelvins outside right now, which is approximately zero help in telling me whether or not I need a coat. Or to zip up my fly.

(Notice that in the Kelvin scale, there are no degrees. That’s because in extremely cold temperatures, that little circle thingy folds completely in on itself and disappears.

See? When you’re flirting with absolute zero, even the measurement units get shrinkage.)

While absolute zero isn’t physically possible to achieve — stupid sexy laws of thermodynamics — you can get pretty close. As in, trillionths of a Kelvin close. Scientists can do amazing things with window fans and ice cubes, apparently.

And when they do, spooky quantum mechanical things start happening.

One of these is superconduction, where electrical resistance in supercooled materials suddenly drops to zero. Another is superfluidity, where viscosity gives up in the cold and goes home. Weirdest of all (and sometimes superfluid) are Bose-Einstein condensates, an entirely distinct state of matter which was first predicted by Albert Einstein and a pair of surround-sound speakers.

(I kid, I kid. Bose was an amazing guy — self-taught, genius and deservedly celebrated. Maybe I should have said “first predicted by Satyendra Nath Bose and a subpar bagel chain”.

Or neither? Probably neither. Moving on.)

Oddly, it’s possible to create a system with a temperature below absolute zero. Oddlier, this system is not only “hotter” than it was before, it’s also hotter than anything else in the universe, based on the physics of heat transfer.

I’d like to tell you this is just like freezer burn. I would. But I don’t think it’s anything like freezer burn, and I have no idea how it works. (And some scientists challenge whether it’s true at all.)

Maybe science thermometers are circular, so the bottom of the scale connects back to the top? Like how some people are so ugly, they’re attractive? I don’t know. Ask an ugly quantum physicist.

So the next time you find yourself trapped in a walk-in freezer (244 Kelvins), sunbathing in Antarctica (190 Kelvins) or drifting in the cold vacuum of space (2.73 Kelvins), just remember that it could be worse. It could be absolute zero.

Well, not quite absolute zero. But really, really close.

Actual Science:
PBS / NovaAbsolute zero
New ScientistWhat happens at absolute zero?
UColorado Boulder / The Atomic LabTemperature and Absolute Zero
Science NewsHottest temperature ever measured is a negative one
MIT NewsIt’s a negative on negative absolute temperatures

Image sources: French Tribune (freezy zero), Betty Draper Looking Pissed (just what it says), Candy-Coated Razor Blades and FanPop / The Office (Mindyjuice! Mindyjuice! Mindyjuice!) and Business Insider (“Shrinkage!”)

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