Wait—I’m in the same building with a bunch of chemists

I’m having second thoughts about the virtues of proximity to my colleagues of that other discipline after watching this video of people plunking alkali metals into water. Cesium looks…interesting.

Fortunately, my chemistry pals aren’t British, or I might have trouble understanding their comments. What the heck does “the dog’s nuts of the periodic table” mean, anyway?


  1. Robert says

    In my high school’s AP chemistry class we watched a home made video of a friend of our teacher dropping large quantities of lithium and sodium into a lake at a mining site (it was already contaminated, so it shouldn’t cause any damage to the ecosystem). It was a cool video, though the best part came when a chunk of the stuff shot into the air, with one of the guys yelling at the camera man (chuck) to look up in the sky. “Up Chuck! Up Chuck!”

    When you’re 16 and its 7 in the morning, that kind of humor is brilliant.

  2. JW Tan says

    Dog’s nuts = dog’s bollocks = something really really nifty

    Bollocks = crap = hogwash = nonsense

    See Samuel L Jackson, The 51st State.

  3. Chris says

    The dog’s nuts must be great, he spends so much time licking them.

    At least, that’s how I heard the expression explained. Who knows if that’s the real etymology?

  4. NJ says

    Hmmm, the host complains that “they” wouldn’t let him have any francium. I suspect the real reason is that the longest lived isotope of francium only has a half-life of 22 minutes, which is why we couldn’t get any for our syntheses…

  5. Ken says

    Makes you wonder why more rednecks don’t become scientists. learn stuff, get paid, and cause explosions. It’s hard to top that.

  6. Dave Godfrey says

    Both the Caesium and Rubidium reactions were faked. When they dropped it in the lumps sank and fizzed, rather than exploding as they’d hoped. So they got some dynamite and blew up the bath. One of the genuine scientists one the show was annoyed and leaked the story to the Guardian.

  7. says


    No chemical reaction I would say, just physical processes loads of CO2 getting of :-) and getting some coke out in the way.

    Real nice it’s NaK alloy (liquid). We used it to dry some solvents (toluene and the like) and had an accident once with the residues. The ceiling was never the same after that.

    For other solvents we used sodium wire; once somebody forgot to destroy the remains of the Na wire on a flask. That was when I was an undergrad student, so a long time ago, and we just disposed everything on the sink with loads of water. The cleaning lady emptied the flask on the sink and …cabum!

    I am chemist, by the way. During my PhD work my neighbours never complained about the explosions, only the smell, specially when I used phosphines and thiols…

  8. says

    In the previous series they blew cars up using thermite.

    The Pilgrim Fathers obviously left before such language developed. Mutt’s nuts, dog’s bollocks, donkey’s cock, kipper’s knickers, cat’s pajamas all mean ‘good’. Say something is ‘the dog’s’ and or simply ‘it’s the bollocks’ people will know what you know mean. But describe something as ‘bollocks’ without the definite article and that’s pejorative. A kipper, by the way is a split and smoked herring not noted for wearing lingerie. Chris, have you not heard the joke:
    Q. Why does a dog lick his balls?
    A. Because he can.
    And having taken Pharyngula into the gutter, I bid you good night.

  9. BlueIndependent says

    If you hang araound British news sites like The Register, you’ll also see other colloquial canine references, such as “world+dog”. That one is typically used as a stark way of speaking about the majority of the public in reference to some current event.

  10. says

    Ooh yes, thiols are very stinky, as are primary amines such as the appropriately named putriscine and cadaverine.

    I love chemistry! Though I was never really into blowing stuff up. I like finding out what’s in stuff, though.

  11. Coragyps says

    Rubidium/caesium alloy is liquid, and one of my fellow grad students found that it would detonate on contact with Teflon. In an argon atmosphere inside a $2000 glove box, yet. He was surprised more than hurt.

  12. Unstable Isotope says

    The reason chemists do these demonstrations is so that students will see what happens, and won’t be tempted to do it themselves. The furthest I’ve ever gone is sodium/water.

    We had an instance on time of AlCl3 spontaneously exploding. AlCl3 is a strong Lewis acid used in some organic reactions. We had an old bottle in one of our hoods and apparently enough water got in that it made enough HCl to break the bottle. The grad student in the lab at the time was really surprised.

  13. beccarii says

    I suspect that 10 g of Rb (the amount claimed for the bathtub demonstration) would do more than fizz; I would expect even 10 g of K to produce quite a bang (much smaller quantities can do that, when plunked into water). Tiny quantities of Cs smolder, crackle and pop, then rapidly burst into flame in air (a serendipitous discovery…). The temptation to further explore such reactivity is severely limited by cost. Cs is a lovely element, though – it has a light gold color, and is molten a bit above room temperature – a beautiful thing to contemplate, within a sealed ampoule.

  14. j a higginbotham says

    [$2000 sounds like a pretty cheap glove box!]
    Even with those slow-dissolving casings, I would have dropped them in via remote control; something where you just pull a string would be easy to do.

    Quite some years ago we had several pounds of excess Na and K thumb size pieces under oil. We took them down to the Mississippi River and tossed them in. Nice, but not spectacular.

  15. says

    Ah yes. Reminds me of the time in high school when a bunch of us were in the chem lab by ourselves. We built a rig to use the reaction creating acetylene gas to squirt water all over the lab. That left us with … a big beaker full of acetylene. Our next bright idea was to light it. Huge flames to the ceiling, but we lived to tell the tale. It’s a wonder any of us survive to adulthood.

  16. Coragyps says

    “[$2000 sounds like a pretty cheap glove box!]”

    1970’s prices. I failed to adjust for inflation.

  17. says

    I liked this video too :) For the curious, the reaction for any alkali metal (Lithium, Sodium, Potassium, Rubidium, and Caesium) with water is:

    M + H2O -> M+ + HO + 1/2 H2 + Heat

    The reaction is the transfer of an electron from the outer valence shell of the alkali metal to a proton (H+) in water, making 1/2 of a hydrogen atom (or neutral H radical, if you like).

    The explodey character of the reaction comes from the increasing zeal with which these metals give up their electrons. More heat=more tendency to explode the hydrogen produced (this is the flame you see; alkali metals will burn in air but it’s probably mostly hydrogen burning).

    Lithium doesn’t barely fizz, sodium is only dangerous in that people try dumping a quarter gram of it in the water and assume 25g will be safe, potassium is getting bad enough to worry, and rubidium and caesium are the kind of things I only ever want to see under ampoules.

  18. says

    sodium is only dangerous in that people try dumping a quarter gram of it in the water and assume 25g will be safe

    It’s also dangerous in the sense that students have this natural tendency to stick their faces right over the top of the beaker or test tube their tiny chunk of sodium is puttering around in. Combine this with the fact that even small chunks of sodium can at times (usually about once a semester, it seems) leap straight into the air from the surface of the water in the beaker or tube. Even with safety glasses, a facefull of tiny sodium bits isn’t healthy.

  19. says

    Too true. Honestly, the only alkali metal I’ve ever put in water is lithium. I was thinking more of Theodore Gray’s sodium party (google it, I’d rather not put in a link and have to wait for approval), where they dumped it in a lake.

    Lithium is funny. It’s not so explodey as far as the alkali-metals-in-water thing goes, but it’s a good enough reducing agent to break aromaticity in a Birch-type reduction. Also, it’s the only alkali metal that has the ability to fix dinitrogen (as far as I know). A chunk of lithium fizzing away atop water will give off a bit of ammonia fumes. Apparently, enough lithium, stored under air, will generate enough Li3N that, if enough moisture is present, it will generate enough overpressure by the reaction:

    6Li + N2 -> 2 Li3N –6H2O–> 3 LiOH + 2NH3

    to burst a closed container (generating twice as many ammonia molecules as dinitrogens). It is also absurdly light (as you might expect from its diminuitive atomic weight). Lithium metal will actually float on mineral oil, which is weird to watch.

  20. JScarry@johnscarry.com says

    This is a complete fake and has been exposed by Ben Goldacre on his blog. Basically, nothing happens with the heavier metals so the producers faked it with explosives.

  21. says

    Rubidium and caesium will happily explode, but maybe not quite as much as I imagined. Theodore Gray apparently looked into it and concluded that yes, it’s explosive, but the higher weight of Rb and Cs means that the stoichiometry by weight changes quite a bit (i.e., much less hydrogen is generated, see here.)

    I’m still not going to play with Rb and Cs.

  22. Xanthir, FCD says

    Nod to JScarry. The video was a fake, at least for the heavier elements.

    The heavy stuff reacts fine, it just clunks to the bottom much too fast. When it does that, any explosion is massively muffled by the water.

    So, they faked it. Check out http://www.badscience.net for Ben Goldacre’s piece on it.

  23. hexatron says

    This bought back a memory of Brooklyn in the 1950’s.
    I was about ten. I had a slightly older friend who was into chemistry (he became a chemist), and had a quite well-equipped laboratory, including several 2-cm sized chunks of sodium metal in a jar of kerosine, the accepted way to store it (the metal develops a waterproof wax coat).

    The fourth of july was extremely rainy. Normal fireworks were out of the question. So we took a chunk of sodium, twisted it (to break the wax coating, and tossed it about 25 feet into a puddle. It provided a sodium-yellow firework about ten feet high and 8 feet across. Very pretty.

    How does _anyone_ become a chemist today? Contemporary chemistry sets are totally castrated, and a kid just can’t get ‘good stuff’ anymore.

  24. Captain Sunshine says

    Robert –

    I have my old teacher’s copy of the Chuck tape. Where did you go to school? The teacher in that video made a new one several years ago with another crazy chemist, one Lee Marek from Illinois. The camera work is better.

    There’s a clip I’ve seen on a couple of ed tapes from Britain, in which all the alkali metals (except Fr) are dumped in water. The cesium blows out the side of the dish. Pretty nice bang. The metal piece did go underwater quickly (with a little help), but the water tamped the blast and directed it into the walls of the container. Maybe this is where the Brainiac got the explosive idea from. Who knows?


  25. says

    No wonder women are under represented in science. The one woman we see close up in this video is holding up a placard and has her tee shirt tied up under her breasts. Must have been the influence of that Aussie conference with the balloon entertainment.

  26. G. Tingey says

    Of course, if you want reeally big explosions, you nedd …
    a Physicist (he he, he, Strange loves we have … )

  27. DrFrank says

    As others have pointed out, the last two explosions are faked as they were actually less impressive than sodium and potassium.

    If you want to see the real thing, go to TheodoreGray.com: there’s some great videos

  28. Dunc says

    Oh come on! We’ve got loads and loads of really good science programming in the UK, and you pick freaking Brainiac? Piffle and balderdash!

  29. says

    Someone I knew was doing something with sodium once. He cut off a small bit of the sodium and was putting the rest of it back when he tripped and dropped the sodium into a bucket of water.

    There was also the time that someone I was working in the lab with finished up whatever he was doing with very carefully buffered very basic cyanide solution and was about to throw it down the sink. Someone actually tackled him to stop it. That would have been less explosivey and more deady.

    Or the time someone tossed some very reactive thing down the drain because he had made it a bit wrong and had to remake it. But it’s no less reactive so fireball!

  30. DrSteve says

    While a chemistry undergrad I was weighing out some sodium hydride (NaH). The phone rang so I stepped away from the balance and answered.

    When I came back the fine grey powder had turned to grey mush (very hydroscopic stuff on a very humid day). Starting over, I took the weigh-paper to the solid waste container – not remembering I had just dumped a bunch of used (and therefore wet) desiccant (sodium bicarbonate?) in there.

    Kaboom! – like flash paper in a magic show.

  31. KevinC says

    Put a sillhouette of a male dog on a periodic table with its nose facing the noble gases and the dogs nuts will be around Cs. Just a crude way of saying on the bottom left of the periodic table.

  32. says

    When I was in high school chemistry I wanted to do NaOH + H2SO4(aq) -> H2O + Na2SO4 (aq), but was not given permission … :(

    I’ve always wondered about extreme acid-base reactions …

  33. Ross says

    One thing you can say in Braniacs favour – it will keep a class of bolshy 14 year olds quiet for a few minutes. It’s interesting though – do you show them the actual, less spectacular, reaction, or show them the faked one which hammers home the increase in reactivity more effectively?

  34. Jdurg says

    Yeah, the reactions with Cesium/Rubidium and water are kind of anticlimactic. Honestly, I believe the reaction of potassium and water is the best one of the bunch. Potassium is far enough down the group to provide a lot of bang for the buck, but it’s up high enough to give you a little bit of time to get away before the reaction truly takes off. Plus it won’t hurt your wallet too badly to throw ten grams of potassium into a pond. (Rubidium and Cesium are just too nice looking to throw away).

    Sodium makes a pretty good bang, however. When I first started collecting elements many years ago I was on a binge of buying the heavier precious metals. Elements where two ounces wasn’t a whole lot of visible metal. In the middle of all these Rhenium, Platinum, Iridium, Osmium purchases I picked up some sodium metal. The thing is, I foolishly bought two ounces because I was shocked to see a metal I needed that cheap for two ounces. I completely forgot that two ounces of sodium is a LOT of metal. So I’ve spent the past few years trying to get rid of the excess 50 grams or so that I have. Last year I went to a cabin out in New Hampshire which was right on a lake. Hehe. I also went with two chemists who had access to a bunch of Na as well. We must have gotten rid of about 4 ounces of sodium that weekend. We kept taking chunks the size of a D-battery and throwing them into the middle of the lake. After a good 15-20 seconds of fizzing the lumps would explode into a mushroom cloud of orange-yellow fire and NaOH smoke with the lump finally hitting the lake surface again a few seconds later and catching fire immediately. Amazing reaction to see.