Bagged Water in Space Has Weird Bubbling Behavior

I'll admit to being a sucker for just about any 'in space' video.

Here we see - and the space.com article explains - air bubbles not separating from the water surrounding them in a plastic bag 'in space'.

It looks impossible but makes absolute sense because it's not the IMFs that separate water from air on Earth's surface but rather the pull of gravity. Gravity pulls more strongly on the more dense water, so the water goes down and pulls together to 'push' the air upward.

No gravity, no pull...no buoyancy...no separation.

How cool is that?

WashU Expert: The global helium shortage hits home

Source - https://www.thoughtco.com/why-do-helium-balloons-deflate-4101553

It's been a decade or more since I first started hearing about a pending helium shortage.

But I didn't notice anything since then.

Sure, Party City posted something about the helium shortage, but I can't remember that last time I bought a helium balloon. I don't care about Party City being able to fill balloon orders or not.

We don't, admittedly have the most reliable helium 'production' system.

Three main sources produce some 75 percent of the world’s helium — sites in Qatar, Wyoming and Texas — > according to gas industry publication Gasworld. In fact the U.S. has for decades provided much of the world’s supply (from cnbc.com)

...and...

A versatile gas, helium is primarily used in electronics and semiconductor manufacturing and is particularly important for medical imaging, such as magnetic resonance imaging (MRI).

Helium is used as a cooling agent in MRIs and in manufacturing processes. Because helium is stable and does not react with other elements, it is also used in the making of semiconductors to create a contamination-free environment.

Still, the biggest consumer use of the gas is in party supplies — and that area is being hit especially hard by the shortage. (again, cnbc.com)

...

[A]nywhere between 50 and 200 of Party City’s 850 stores don’t have any helium in their tanks at any given time. (again, cnbc.com)

As I write this, Party City has announced the closing of 45 stores nationwide, including the one nearest Princeton High School, but we're going to be out a lot more than party balloons in the scientific realm unless we can either produce more helium (an unlikely outcome based on what I know about noble gases) or use it more efficiently.

Source - https://boingboing.net/2019/05/10/helium-shortage-deflating-part.html

As with so many things, I blame Cleveland.

World's Lightest Solid!

I've written about aerogel before (and perpetually mention the demise of my one piece).

But I haven't shown a video that uses a FLIR camera (1:00) to show the heat zones as they insulate a chocolate bunny from a bunsen burner using aerogel, where they show the industrial process of making aerogel (5:25), or especially where you actually get to see a supercritical fluid through the window (6:25 - the absolute highlight for a teacher who used to teach phase diagrams in AP chemistry), or where you get to see a mid-process 'wet' aerogel filled with alcohol (4:50).

If you happen to follow both of my blogs, you might see this double posted because of that supercritical fluid bit.

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The above the line stuff is what I wrote over on my material science blog because those folks care more about material science. Here, though, we care more about the chemistry, so I'm going to focus on the idea of a supercritical fluid.

The basic definition of a supercritical fluid is, from Wikipedia, "any substance at a temperature and pressure above its critical point, where distinct liquid and gas phases do not exist. It can effuse through solids like a gas, and dissolve materials like a liquid."

See, the phase of a material depends on its pressure and temperature. We all know that water can exist as a liquid (between 0^oC and 100^oC at normal atmospheric pressure). Most folks know water can exist at even higher temperatures if it's under pressure (like in a pressure cooker). Below 0^oC at normal atmospheric pressure, water turns into a solid, but if pressure is applied (like underneath the blade of a sharp ice skate) that solid turns into liquid without warming above 0^oC.

If we graph all that, we get...

Source - http://wps.prenhall.com/wps/media/objects/4678/4791085/ch10_11.htm

In reality, water has a bunch of different solid crystal structures, so we could complicate things like this...

Source - http://ergodic.ugr.es/termo/lecciones/water1.html

...where each Roman numeral corresponds to one of the different, atypical crystal structures for ice. There isn't any real ice-nine, thankfully.

For carbon dioxide, as we see in the video up top, the phase diagram looks like this...

Source - same Wikipedia article for supercritical liquid as above

See that grey-blue area there, where it's not grey, and it's not blue but is rather a blend of them?

That's what we're seeing in the video.

And I've never seen it before.

Red Cabbage Chemistry - Sick Science! #105

...but the smell...

If you don't want to buy universal indicator, make yourself some red cabbage solution. It's cheaper. It's available at your local grocery store.

And it smells like cabbage.

You can - if you're a school - also buy cabbage extract powder from some science suppliers.

It's a great way to pass an afternoon...or just to entertain yourself while your significant other makes red cabbage to go along with the smoked sausages if you - like I - don't eat cabbage.

Results after the jump...in case you're too lazy to do the experiment yourself...

Revealing Van Gogh's True Colors

Current version (left) and digitally recolored version (right) from the SciFri story.

I have to confess that I hate Science Friday.

I like the idea of a weekly hour of science content on NPR, but I can't stand Ira Flatow. He's obnoxiously curious, interrupts his guests with inane questions, and just generally annoys the crap out of me. I prefer the show when he has a substitute host.

That being said, sometimes the guests have fascinating things to say. On this episode, Ira interviews the senior conservation scientist at the Art Institute of Chicago.

It's fascinating that the painting has faded with exposure to oxygen and light exposure and that Van Gogh knew this - not that he knew the chemistry but that he was aware of the fading of the paints overtime and painted in a way to allow for that.

Setting Fire to Glass - The "Nope" Chemical That is Chlorine Trifluoride

"Rocket scientist Dr. John D Clark famously said about the best way to deal with potential chlorine trifluoride rocket accidents, 'I have always recommended a good pair of running shoes.' "

Or, just don't go in the pool in the first place.

Chlorine trifluoride sound like something I absolutely, positively do not every want to come even remote contact with.

I love the concept of storing chlorine trifluoride inside a steel container that's been already fully oxidized with fluorine gas. In chemistry class, I mention the storage of fluorine gas similarly and use the analogy of asking the fat kid to hold onto - but not eat - your pan of brownies. The only way to do that safely is to already feed him brownies until he's sick to his stomach of brownies. Yeah, you've lost a whole bunch of brownies along the way, but your final pan of brownies is gonna be safe.



If the little dalliance in the middle of the video about hydrofluoric acid intrigues you, check out this post of mine from a few years back about hydrofluoric acid treatment.

Making metal crystals from Pepto-Bismol

Admittedly, at first I looked at this video with some excitement, thinking that I might be able to use the procedure to demonstrate reduction of a metal in my material science class - or in chemistry.

But the procedure is insanely problematic and long and scattershot in its success. There's no way that rookie science students could perform this with any level of success.

It is, however, frickin' cool to watch.

Plus the video is insanely high def.