The chemistry of pyrotechnics (shorts)

After the fireworks video a couple of weeks ago, I went hunting more videos to explain the chemistry of pyrotechnics, and I found a bunch of them.

We'll start this week with the shorter videos.

The one above is the most comprehensive of the short (10 min or less) videos I've found. It explains a bit of history, some of the structure of, the chemical reactions taking place in, and the colors produced in common fireworks.

Start with that one. 

It isn't, however, a very pretty video. It's a lecture with an animated hand writing and drawing on a digital white board. Not the most exciting of the videos.

How Lava Lamps Are Made | The Making Of

Lava lamps, still relevant today.

So, molten blob of glass blown into bottle shape. Check.

Two questions there...one, we see the workers throw away two bottles in the maybe ten second film clip. That seems a really high failure rate or an incredible fluke. Two, I wonder what kind of glass they're using. I would think soda lime would risk cracking from the uneven heating from the bulbs versus the air.

Metal pieces spun and polished. Check.

If you want to see something about how dislocations allow for that metal spinning, check this out.

Fill 'the liquid' in the bottle along with a metal spring. Check.

So we know one of the liquids is 'colored wax' meaning it had to be nonpolar. I assume that the other liquid is something polar. I get that the family makes sure the trade secret is kept secret, but I desperately want to know if at least I'm correct about the polarities.

Maybe I should just stare at the lava lamp I own for a while to calm down.

The Last Molecule

 

Source - https://xkcd.com/2552/

See it's funny because there's no way that chemistry - or any science, really - will ever be 'complete'.

I'll quote here from the explainxkcd.com entry because it's really well written (as is usually the case)...

"[T]this may be a reference to a quote from around 1900, often attributed to Lord Kelvin or Albert Michelson: "There is nothing new to be discovered in physics now. All that remains is more and more precise measurement."

...

"In real life the number of ways to arrange atoms into molecules grows combinatorically with the number of atoms in a molecule. Since molecules can be extremely large (up until the point where gravity takes over and initiates nuclear fusion), the number of possible combinations is much much larger than the number of particles in the observable universe, making the full cataloging of all molecules impossible. Thus, a "final molecule" cannot be reached. In addition, chemistry is the study of the interaction and changing states of atoms and molecules, not simply the cataloging of all specimens of molecule. Even if we did have a list of every molecule, there are a far greater number of ways to continue studying them, so the field would still be nowhere near completed."

...

"As readers are aware of this, part of the humor comes from the very high percentages given to the different fields. [...] Another part of the humor is the precision."

Jokes for nerds, folks, jokes for nerds!

Isotopia: An exposition on Atomic Structure, Written in the Form of a Mime

Muriel Howorth (right) and Beverly Nichols, from Wikipedia

To quote from AtomicGardening.com which quotes from Time's October 30, 1950 issue...

Before a select audience of 250 rapt ladies and a dozen faintly bored gentlemen, some 13 bosomy A.E. Associates in flowing evening gowns gyrated gracefully about a stage in earnest imitation of atomic forces at work. An ample electron in black lace wound her way around two matrons labeled "proton" and "neutron" while an elderly ginger-haired Geiger counter clicked out their radioactive effect on a pretty girl named Agriculture. At a climactic moment, a Mrs. Monica Davial raced across the stage in spirited representation of a rat eating radioactive cheese. Mrs. Davial, it was noted in the program, had "recently returned from a trip to Tibet" and hence presumably had a nice understanding of these things. A small boy named Bunny May was on hand to guide recalcitrant atoms into their proper places.

Holy poop, this description is of "Isotopia: An Exposition on Atomic Structure, Written in the Form of a Mime" by Muriel Howorth (more on her in a bit). It seems that the 'ballet' was only performed once, but thankfully the hand-typed 'script' was donated to the British Library and preserved there. You can check out most of the text (some of the scans seem to have been cut off) on the Atomic Gardening website.

I love that atomic energy was such a fad in the mid 20th century, absolutely love it.

I wonder if I could convince Mr Fielder to have his theater students perform this someday...

Watch this beetle walk upside down underneath the water’s surface | Science News

Not much explanation in that video, luckily the Science News article does contain a little more explanation, mostly landing in the 'more research is needed' camp.

See, the beetle is walking upside down on the surface of the water but underneath the water. Apparently snails can do this, too.

The Engineering of the Drinking Bird

I would make a Darkman reference, but I'm guessing nobody would get it.

Maybe a Simpsons reference would be better.

This video goes through the liquid evaporating on the head of the bird...causing cooling in the head...causing a decrease in pressure in the head...causing the lower bulb's greater pressure to push the liquid into the head...causing the center of gravity of the bird to shift slightly forward...causing the liquid in the base to drop below the level of the inner tube...causing the vapor from the bottom bulb to flow through the tube and equalize pressure between the two bulbs and liquid to shift back down...the process repeats as long as the bird'd beak can 'drink' to stay wet and - as Bill points out - the humidity is low enough to allow evaporation.

This is also how hand boilers work.

I'd never heard the temperature difference's connection to heat engines (referenced previously on the blog). That's a nice connection there, Bill.

Small Bottle, HUGE Fireball (How Flame Jetting Works)

I've mentioned the dangers of methanol before, often before.

This video isn't specifically about methanol, but it is about flame jetting, a situation similar to the accidental ignition of methanol in many of those lab accidents. In many of those accidents, a bottle of flammable liquid (usually methanol) is poured onto or near an open flame. The fumes from that liquid catch fire and push the rest of the now burning vapors out of the bottle....violently out of the bottle. 

Don't squirt lighter fluid onto an already burning fire.

Don't pour alcohol - drinkable alcohol - onto a burning drink.

Don't mess with methanol at all.

The rainbow flame demonstration

Repeat after me, folks, "don't mess with methanol."

This demo (procedure here) is done using ethanol which would be way safer - but not totally safe, of course. The colors aren't quite as brilliant and clean as those done with methanol, but as I've said before, methanol isn't remotely safe to use here.

I do wish that I had access to the CLEAPSS document, however, but it's behind a login wall. It's apparently free for schools in Great Britain but not 'round here.

I promise this story about microwaves is interesting.

"By a strange twist of fate, the microwave was invented to meet a need to heat hamsters humanely in 1950s laboratories."

Seriously, that quote was the initial spark that lead Tom Scott down the rabbit hole to eventually create this video.

And I'm thrilled that it did, because the quote is kind of true. 

It wasn't the need that eventually lead the first person to create a commercially viable microwave oven, but it certainly was a need that a British scientist had when he and his colleagues were experimenting on cryogenic freezing of mammals and then bringing them back to life.

The story - and the interview with James Lovelock himself - is brilliant and incredibly weird.

Restoring Rothko | Tate

I don't have a clue what the vandal wanted to say about art or Rothko by defacing this painting. I've read an interview with him soon after the incident, and I still don't know. It looks like he was given two years in jail for the crime. That's appropriate because that's about the same length of time it took conservators to restore the painting.

The amount of science that goes on behind the scenes at art museums is amazing to me. I was lucky enough to tour the conservation lab at the Indianapolis Museum of Art, and it was one of the more impressive 'factory' tours that I've been on, just fabulous stuff going on there.

This video goes through the process that the conservators went through in trying to restore the damaged Rothko. At a very base level, the technique is nothing more than a solubility question. Find something (we can see at 8:39 that the chosen solvent for the black areas was "1 pt (10 mls) EL / 1 pt (10 mls) BA", but I have no ideal what EL and BA are) that dissolves the vandalizing ink but doesn't dissolve the original painting. Apply that solvent carefully, repeat and proceed.

But the art that's involved in that is - to me - as impressive as the original art making. 

Restoration can be horribly done when the materials aren't understood, but clearly these conservators are brilliant at their job.

By the by, if you want to learn about the paintings themselves, you could do a lot worse than this video.

Flesh-Destroying Chromic Acid - Periodic Table of Videos

In posting this video, I went looking for the original video that I was sure I had posted on the blog. Turns out I hadn't, so I'll go ahead and post that below. Might be worth watching it first, though you will get the general gist by watching the above video.

I remember chromic acid being around the stock room of Wabash's chem department - and also around Pru Phillips's stock room when I student taught for her. Pru kept the chromic acid around for when her glassware got too stained for acceptable use.

I'm passingly familiar with the dangers of chromic acid, however, so I don't have it around, and Flinn Scientific doesn't even sell it anymore.

After watching this video, I think that's a good choice on their part.

The Difference Between High Explosives and Low Explosives

I never considered that high explosive was a technical term and that consequently there must be low explosives.

To quote Stephen Miller, the explosive expert from the video...

• Explosives are a mixture a fuel and an oxidizer.
• With low explosives these are roughly mixed together...when a low explosive reacts, it's a thermal reaction
• A high explosive is also a mixture of a fuel and an oxidizer...down on the molecular level, the atoms [?] of the materials are in such close proximity that they are linked together within the molecule and...they can react a whole lot faster...It's actually a shockwave reaction.

I didn't know those distinctions, and I really didn't know that high explosives can be safer for transportation because they're more stable, requiring a shockwave to set them off.

So you've learned to teleport

Yeah, suck it, Nightcrawler...Pixie...America Chavez...Lockjaw...

You should be making perpetual energy for the planet, and you're just off saving the universe or fighting crime.

The 2021 Nobel Prize in Chemistry - Periodic Table of Videos

I know, a rare Sunday post.

I figured it wasn't worth posting this explanation of this past week's Nobel Prize in Chemistry in January when I next had an open spot in the queue of scheduled videos.

So check this out. It's one of the better explanations of why asymetric organocatalysts are Nobel-worthy.

How Professional Fireworks Work

Probably twenty years ago I took a week long workshop "Chemistry of Pyrotechnics" at Miami University in the summer. It was a great explanation of the science that goes into creating everything from tiny backyard sparklers all the way up to giant fireworks shells.

The course was taught by people who normally taught science to fireworks makers, and they said that the workshop was their first time teaching the fireworks side to people who already knew the science. That made for a really interesting cross-educational experience.

Coincidentally, it turns out that Ed Escudero and Beth Eddy - both of whom I would later work with through ASM - took the same class.

The above video takes you through more of the mechanics of a large, professionally made pyrotechnics shell than it does the chemistry of pyrotechnics (I'm going to look for that video in a minute), but the mechanics includes a bunch of chemistry from controlling the rate of a reaction to producing the various colors. 

And I just put in a request to get a copy of this textbook from the University of Akron library. Thank you, OhioLink.

Opening a Soda on the Ocean Floor

Chris Hadfield is among the best of us.

He's a fickin' astronaut, a pretty nifty quitar player, a hell of a pilot, a great science communicator, the father of an interesting YouTuber, and a good sport.

In this video, Chris doesn't do a lick of science explaining, but he does demonstrate the fact that if you're going to shake up a soda can and immediately open it, you'd best be under double atmospheric pressure at the bottom of the ocean.

To fill in what Chris doesn't explain, the fizzing is largely a result of this equilibrium...

H₂CO_{3 (aq)}  ⇌   H₂O _(l) + CO_{2 (g)}

At normal atmospheric pressure that CO₂ pressure is low, so the reaction shifts to the right until it reaches equilibrium and your pop is flat. Allowing the pressure to build up in a sealed container - keeping the coke bottle closed up - stops this from progressing because eventually Q = K. So does cooling down the tonic container because the reaction is exothermic and endothermic reactions (the reverse reaction, keeping the gas dissolved in the solution as carbonic acid) are favored at colder temperatures.

But at the bottom of the ocean, there's apparently a high enough CO₂ pressure in the atmosphere that the soda doesn't immediately fizz up.

Liquid Crystals Painted On Heat Pipes

So much science...phase changes due to pressure and temperature changes...constructive and destructive interference colors...thermal expansion made visible via liquid crystals...

I feel like I need to get me some of those heat pipes.

Can You Stop Water From Expanding When It Freezes Into Ice?

Chris Dyer graduated from Princeton in the spring of 2004 and died in Iraq in 2005.

I mention this because I remember doing this demonstration with Chris and his dad in the side yard of the old Princeton High School building. The AP chemistry students that year had seen an 'ice bomb' sold by Flinn Scientific. The thing they were selling was nothing more than an elbow of steel pipe with two screw caps. As the water freezes in the pipe, the water expands and eventually causes the pipe to explode.

I told the students we couldn't do that because I didn't have access to dry ice. I didn't mind spending the $20 or so (Flinn no longer sells that item, so I can't check the actual price) on the pipe, but I didn't have the dry ice or liquid nitrogen necessary to freeze the water inside it.

Chris piped (sorry) up that his father worked at a lab and had easy access to dry ice. So I ordered the pipe. John Dyer took the day off and came to school with his son.

And we blew up a pipe in the side yard.

Stupidly - because it was less fun to see - we blew it up inside a 3/4" plywood box. Smartly - because nobody got hurt and I got to keep my job - we blew it up inside a 3/4" plywood box.

That's my lasting memory of Chris Dyer.

And I'm really glad that The Action Lab guy moved his safety shield in front of himself and his camera just in time. I was worried throughout the first part of the video.

(Sorry for this being a bit of a downer post. Feel free to make a donation to the Chris Dyer Memorial Scholarship fund - either of them.)

Cocoa Powder That Can't Get Wet in Milk

We do this experiment in honors chem at Princeton HS when we study intermolecular forces.

The general response that I get from most students the first time they do the experiment successfully is general grossness and stunned. The peeling of the 'skin' of the cocoa is just so gross.

We, admittedly, don't do the demo with the lycopodium powder, but we might be doing that in the future. We do something similar to that with Magic Sand, though.

And we certainly don't do the demo with the vacuum pump. I have a vacuum pump, though. Interesting. Might be worth trying in the future.

And the flammable water at the end...hmmm...

Why pickles make great light bulbs

I hope this goes without saying, but do not try this at home.

It's been a few years since I've done the electric pickle demonstration. Maybe I should do that again next year.

In all honesty, I sometimes forget how cool some of the demos that I've done through the years are. It's so easy to forget which demos go where and to just accidentally let them slide into forgetfulness.

Let's light a pickle next year, folks.

And, yes, I'm rethinking my dislike for The Action Lab.

Is It Actually Possible To Cut Glass With Scissors Underwater?

Maybe I need to change my mind about The Action Lab.

I initially clicked on this video fully prepared to be snarky about the clickbait title. "Yes, obviously it's possible. Otherwise you wouldn't have made a video about it."

And then we got to the bonding explanation of why it's possible at 3:35 in the video.

On a whiteboard, the host - whose name I should probably look up - shows how the bonding in the silicon dioxide covalent network of the glass is broken as the glass preferentially bonds (or adsorbs as the host says) to the water molecules accelerating the crack growth. This apparently 'lowers the energy needed to break the silic[a] by a factor of 20', and that's all about activation energy and heterogeneous catalysis.

Turns out that video was way more educational than it had any business to be.

I wonder if this has anything to do with grozing pliers.

Playing with superhydrophobicity

I don't always dig the videos from The Action Lab. I'll admit to that right off the bat. 

The host's voice has an odd cadence and tone that grates on me. The experiments are often interesting and creative, and his science explanations tend to be pretty good. Occasionally it's "I painted a room with the blackest paint" or "...the whitest paint" or "...with mirrors" - all of which are lame, but many of his videos are okay. I just generally don't like them.

But I'm kind of digging his second channel, Action Lab Shorts. The videos are - as the title says - shorter, quicker little hits of interesting science content.

Today I'm going to post five videos, three from his short channel and - after the jump - two from his full channel. You make the call...

All of them show superhydrophobicity.

Why Molybdenum is named after Lead - Periodic Table of Videos

The Professor is back, and he's bringing a solid lesson in etymology.

As you'll find in this video, many elements are named for other elements.

Nickel, for example, comes from kupfernickel in German, meaning that the element nickel was 'demon's copper' or the metal that was placed beside copper by demons making the copper harder to mine.

Ok, actually I can only find two elements named after other elements: molybdenum and nickel.

But still...you should go learn what some of the element's name origins.

Tentacled droplets swim with stored heat energy

Okay, I will readily admit right off the bat that I have no clue what is happening here.

I can describe it using the words of the ChemistryWorld.com article from which this video comes...

Beginning as innocuous oily droplets about 20–40μm across floating in water, these structures take on faceted, crystal-like shapes when cooled to around 2-8°C – even though they aren’t frozen. Then things get really weird. 

Some of the particles’ facets grow while other shrink, producing a variety of geometrical forms such as kites, isosceles triangles and spiked tetrahedra. Then, from some of the sharp corners emerge tentacle-like strands, as if being extruded from a nozzle. As they grow, the strands bend into undulating shapes – and the droplets start to swim, propelled through the fluid by the tentacles’ extension.

What the heck? The tentacles appear as the microdroplets are cooled, propelling the microdroplet forward. Then, as the droplet is warmed again, the tentacles retreat back into the droplet? That's weird.

Luckily, I'm not the only one stumped as to what's happening here. " ‘I have really no idea what is going on,’ [McLeish] admits. "

The world is strange. 

Let's try to keep it that way.

Piezoelectricity - why hitting crystals makes electricity

Heya, Steve. Good to see you back again.

The part of this video that I think I most appreciate is the actual look at the guts of a piezo electric safety lighter. I've used them for a long time and never quite been sure how they work on the inside.

I also appreciate Steve's comments on quarts 'healing crystals' around 1:40. "Don't know if you take it orally or..."

And then we get into the fact that piezoelectricity is dependent on the electronegativity differences in a quart crystal (admittedly simplified in Steve's peanut-butter-jar model). I'm totally duplicating this post for my material science blog because of that explanation.

Chemistry lab fire at Strive Prep school sends 4 students to hospital (and follow-up)

smh...smdh...methanol, folks...just don't use methanol at all.

AT ALL

Unless you are professionally trained in safe handling of methanol - and I'm going to say that I don't feel confident that I'm well enough trained to use methanol safely - don't use methanol in any demonstration.

Yes, it burns nearly colorless making it an outstanding fuel for flame test demonstrations, but that's also the reason it's so remarkably dangerous. The nearly colorless flame is too easy to miss when you go to refuel the flames. 

It's not worth the risk.

Denver 7 did some follow-up stories - including one where they show the rainbow demonstration and discuss the risks and safety requirements. I'll post those videos after the jump.

Exploding Wires & Amazing Molybdenum

I appreciate the playfulness of the Manchester chemists playing around in their videos. They show great curiosity and seem honestly fascinating by the results. The above video shows them running electricity through wires of various metals - copper, aluminum, magnesium, brass, tungsten, gold, molybdenum - in open atmosphere.

Even more impressive to me is their tenacity in trying to explain something once they get unexpected or at least curious results. In the video below, they explore the phenomenon of molybdenum wires producing what they refer to as unduloids - regularly spaced molybdenum blobs - on the surface of the heated wire. 

Quicksilver and Slow Death

 

Source - "Quicksilver and Slow Death" - National Geographic, October 1972

I'm just going to let that picture sit there for a moment.

Feel free to scroll down once you've absorbed the fascination, curiosity, intrigue, and abject terror of the sight of a man sitting on a pool of mercury with seemingly no protective equipment at all.

I'll wait.

That's the picture that sent me down a rabbit hole a few years back. I came across the photo somewhere - I've no clue where other than 'on the internet' - and wanted to track down its origins. Who took that? Where were they? Why were they sitting on mercury? When the heck was it taken?

Eventually I came across a source saying that the image came from National Geographic's October 1972 issue in the article "Quicksilver and Slow Death".

At the time, hunting down the article with images was fairly difficult as I hadn't found full text scans of articles in library databases just yet.

So I headed to ebay and spent about $6 buying a copy of the magazine so I could read the original article.

It turned out to be fascinating.

Here's the original caption for the photo.

Floating on mercury, a veteran miner demonstrates the metal's high density - 13.5 times that of water. Mercury's great cohesiveness prevents it from wetting skin or clothes. Being liquid, however, it penetrates the finest crevices. Once out of the vat, the man turned out his pockets and shed his showed to shake out droplets of theś metal.

The article surveys the historical ideas of mercury...

Arabian and European alchemists deemed mercury one of the two "contraries" (the other was sulphur) that combined deep in the earth to form all other elements.

...the health hazards of mining mercury...

In one room [of the miner's hospital] the walls were lined with powerful lamps, the floor marked with a circular path. "The miners call this the 'beach,' " Don Jeśus told me. "Sometimes a man inhales too much mercury vapor in the mine and develops a tremor. If it's a sever case, the doctors send him here for treatment.

"He strips and walks round and round in the heat, sweating out the mercury. Most respond rapidly and are returned to work. A few don't; they are pensioned."

...and the health hazards of exposure to mercury, particularly from eating contaminated fish, pork, or grain...

Borne by the bloodstream, methyl mercury penetrates brain membranes that bar most other poisons. First, it damages the organ without appreciable loss of cells, then erodes whole pockets of tissue. Worst hit are the brain's visual, hearing, and equilibrium centers, thus explaining the effects of mercury poisoning - blindness, deafness, and loss of balance.

The article closes with this warning, from Dr Alf Johnels, 

"It was a matter of human failure. We cannot see beyond immediate needs: Mercury did the job, so we used it and trusted the earth to absorb in. Not until people and birds died did we find out how wrong we were.

"If mercury were the only pollutant, that would be one thing. But every day we're pouring into our environment tons of other substances - cadmium, lead, industrial chemical like the polychlorinated biphenyls called PCB's. Some are stable and will be with us a long time. And we have no idea what their long-term effect will be.

"We who work in museums know about vanishing species - they are here, as always, then one dat they are gone. Their environment has changed.

"Only if we think in terms of generations, and are willing to pay the price of keeping the world clean of our our foulings, can we have confidence that man will not join that list of vanishing species."

If you want to read the full article - it's dated but outstanding - here it is in full.

"Quicksilver and Slow Death" - NatGo - Oct 1972 by phschemguy on Scribd

The secret of the aluminum can: what is it hiding?

That's some impressive can polishing right there.

This video from MEL Chemistry shows how to reveal the secret polymer liner that lives inside every pop can (or Coke can if you're from Southern Indiana like your friendly neighborhood blogger is) using 'drain cleaner.' I assume it's something like Drano, a very concentrated solution of primarily sodium hydroxide. 

I do this experiment in class using hydrochloric acid in the 3M range, and it works just fine. Aluminum is, however, soluble in both acids and bases (not typical of most metals), so I have heard that sodium hydroxide solutions can produce the same result. 

I would certainly be careful with the 'drain cleaner', folks, because it's some nasty stuff. Weirdly, I'm more comfortable using 3M HCl because it's something I use with fair regularity at school. The Drano, however, gives me a bit of an uneasy feeling. Oddly, though, Steve Spangler's video of the same demo also uses sodium hydroxide as did most of the other videos I found showing this demonstration. That might be because buying hydrochloric acid can be a bit tougher (unless you know it's also called muriatic acid and is available at most hardware stores.)

Either way, be careful if you try this at home, but it's pretty frickin' awesome to see.

Mystery Blue and White Beads

The blue and white bead bottle up there might look familiar to a lot of science teachers, especially the ones who have taken our ASM summer camps. The bottle can be bought from Educational Innovations or from Flinn Scientific (though Flinn's version is green and white).

The bottle is a spectacular demonstration of density and of solubility, both of which are explained by Steve Mould in the above video.

We do a similar activity in a lab in our material science course at Princeton (one we certainly didn't develop but have tweeked to our needs) using preforms and polymer pellets. An extension we particularly like is related to the food coloring demo that Mould mentions in passing near the end. I especially recommend green food coloring. The effects are far more dramatic than the red that Mould shows.

Another extension involves shining ultraviolet light at the bottle. It turns out that - as one of our Utah campers pointed out to me after I'd had the bottle for a decade or so - that the white beads are actually the UV beads that Ed Inn sells. Apparently having a classroom with no windows blocked me from seeing that happen until she pointed it out to me.

I did also find a video showing how you can make one of your own - without the UV beads, however. The YouTuber's full instructions with quantities can be found in the video description.