Fire tornado in slow motion 4K - The Slow Mo Guys

We're not yet to chemical reactions in the course of honors chemistry (sadly, because that's the best chapter, honestly), but this is just too cool to hold off on.

I've done a much, much smaller version of this as an in-class demo to show the effects of increased oxygen on combustion...(not my video, by the way, but about the same set-up and scale)...

I'm Atoms (Scientific Cover of Jason Mraz's I'm Yours)

I'm not a fan of Mr A-Z. I'll admit that right off the bat. He just seems too much like a parody of every fraternity guy who learns how to play the guitar just well enough.

With that being said I do actually enjoy "I'm Yours". It's a catchy song and eminently tuneful. It's a nice little earworm.

This version isn't nearly as tuneful or catchy, but it's far more scientifically accurate, and it lets me continue to be impressed with Derek Muller.

An Invisible Fire

I thought about opening this post with images of hydrofluoric acid burns but decided not to do that. If you're desperate to see gruesome images of horrible skin damages, go ahead and click for the search.

I'm happy to say that I don't have any hydrofluoric acid in my storeroom at school. I have sulfuric, nitric, benzoic, hydrochloric, acetic, malonic, and a few other powdered acids. But hydrofluoric acid scares the mess out of me.

See, I first read the article "Invisible Fire" in Discover almost twenty years ago now. The article tells the story of a renter who didn't know to use gloves with hydrofluoric acid. Within an hour, he was in the emergency room hoping not to lose the use of his right hand.

[S]ulfuric is not the acid to be most feared. That distinction belongs to hydrofluoric acid, a compound commonly used in solvents and rust removers, and so powerful that it can be used to etch images on glass. Although the burn it produces initially causes no blisters or changes in skin color, it can leave behind a scarred limb.

Hydrofluoric acid can severely damage the deep tissues of the body yet leave little trace of damage on the skin surface. It can even kill. People have died after a patch of skin no bigger than the sole of the foot was exposed to the substance.

I am totally fine not ever having to worry about one of my students spilling that on their skin.

Things I Won't Work With

Man, the number of times I've been asked a variation on 'what's the most deadly [whatever]' over my twenty years of teaching has to be incalculable.

I, honestly, have absolutely know idea what the worst acid is (hydrofluoric scares the pee out of me, admittedly). I don't know what chemical I have that's the most flammable (maybe methanol). I don't care which chemical is the most deadly in my stockroom.

I do know, however, that anything that scares a professional scientist - especially one with the respected pedigree of Derek Lowe - scares me.

But I do like reading about dangerous stuff, so I'm glad that Dr Lowe's In the Pipeline blog (now on Science magazine's site) has a tag called "Things I Won't Work With."

I particularly recommend his articles on peroxide peroxides ("Colloquially, I would imagine that the compound is known as “Oh, @#&!”, substituted with the most heartfelt word available when you realize that you’ve actually made the stuff") and azidoazide azides ("Never forget, the biggest accomplishment in such work is not blowing out the lab windows.").

Honestly, though, all of the posts are enlightening and hilarious.

What is Fire?

Fire is awesome.

That's a simple enough answer, isn't it?

This video - with its oddly-voiced, slightly-speech-impedimented (or maybe just a British accent), and weird narrator - explains a bit of the history of elements and then goes through the parts that really make up the fire: fuel, gas, light, heat.

In the end, the answer to the video's titular question is this: Fire is actually the visible side effect of what happens when matter undergoes a change of state by means of a chemical reaction. (at 1:15 in the video)

Lethal Seas - NOVA

Climate change is real and will likely be the biggest single issue for the next century - most of which I probably won't be around to see. So many of our other issues - food scarcity, weather-related natural disasters, political instability - will be influenced by the changing climate that it will become tough to tell whether an issue is caused by climate change or by something else, though, because climate change will simply be an accepted and obvious thing when our current (soapbox warning) crop of ignorant, private-industry-bought-and-paid politicians pass from the halls of Congress.

This program - from PBS's Nova - goes through the effects of increased carbon dioxide levels on the oceans and the life therein. Oyster larvae are dissolving in the more acidic ocean water. Coral reefs are dying in the acidified water. Terapods - a first level consumer and base food in the ocean pyramid - aren't growing. Fish are swimming toward predators after growing up in an acidified ocean.

There's a great animation of the calcium carbonate building at 9:40 and of the formation of carbonic acid at 10:05 after that. The rest of the video is great, too.