Wanna dispose of some sodium? Na.

By Phil Plait | February 22, 2012 12:05 pm

You might think I’m posting this just because of the awesome title above, but in fact it’s for a video that’s even better. I know!

Here’s the scoop: after WWII, the US government found they had some extra sodium no one wanted, so they disposed of it.

In a lake. Full of water. And by the way, it was ten tons of pure sodium.

So yeah, you wanna see this newsreel footage from the event:

Holy crap.

[UPDATE: By a funny coincidence, I just found out that io9 posted a similar article with 10 videos featuring explosive chemical reactions!]

Sodium is highly reactive. It’s way over on the left side of the periodic table, which means it really wants to give an extra electron to any receptive atom or molecule that happens by. Water will happily accept that electron, but at a cost: the reaction creates sodium hydroxide (NaOH) and hydrogen gas (H2). It also generates a lot of extra energy in the form of heat. A lot. And there’s hydrogen around. Remember the Hindenburg?

So yeah. Heat + hydrogen = BANG. Especially when you’re dumping that much sodium into a lake! The explosions generated by this were impressive, to say the least.

In high school we did something like this, though on a very small scale. Our teacher took a tiny bit of sodium and put it in a glass with water in it. Sodium is very light, and floats. It reacted with the water, but far more slowly than in this video, rolling around on the surface. As it did, it released the hydrogen, which is lighter than air (and also warm from the reaction) so it rose. The heat ignited it, and so as the ball of shiny metal sodium rolled around on the water’s surface, a tiny blue vertical flame followed it around. It was one of the coolest things I had ever seen, and probably made my nerdy adulthood that much more inevitable.

Oh, and all that surplus WWII sodium? While that would destroy the ecology of a lake, in this case it was already a heavily alkaline lake with no fish in it. While I wouldn’t say this was a great thing to do, at least they thought to minimize the impact. But cripes: don’t try this at home.

Tip o’ the vent hood to Corante.

Related posts:

Gummis. The Gummis were screaming. (You really want to see this one)
"How do we know he didn’t invent the thing?"

CATEGORIZED UNDER: Cool stuff, Humor, Science
MORE ABOUT: sodium

Comments (45)

Links to this Post

  1. Long enough to reach the ground « slacktivist | February 27, 2012
  1. ragnar

    Why did they dispose of it that way? They could easily have added chlorine from the rather large chemical weapons stockpiles and made 20 tons of salt.

  2. Mike Oliver

    We did this experiment with a somewhat larger chunk of sodium than in your high school. After sputtering around on the surface for a few seconds, it exploded, sending burning fragments every direction like fireworks (yes, this was done outside). Potassium did the same thing, only faster. But I distinctly remember that the sodium produced a yellow flame, and the potassium was purple. So there must be something else going on besides just the burning of hydrogen.

  3. Anonymosity

    This: http://xkcd.com/18/

    I know you already read xkcd (grin) but this one makes me smile every time.

  4. Trebuchet

    Anyone catch the name of that lake? Sounded like “Lenall” or something? If it wasn’t alkalai before, it was after!

    When I took chemistry, in the mid 1960’s, we were supposed to do an experiment in which a test tube was submerged in a tub of water then raised up, mouth down, so it would remain full of water while a small hunk of sodium was slipped under the rim and the student could watch it generating hydrogen. We didn’t get to do it because a student in a previous class managed to let air in while adding the sodium. The resulting small explosion sent glass flying and caused minor cuts. Oops!

    ETA: Found the lake. It’s Lake Lenore. The sodium disposal is mentioned in the Wikipedia article.

  5. Don’t try this at home? Sure, but who’s going to have 10 tons of sodium laying around in their backyard (which has to be dry)?

  6. roger hill

    How about some potassium? ‘k.

  7. Alex Simmons

    I did same experiment at high school too in 1980, but it was banned after my attempt as it exploded big time shattering the glass lid of container over the entire lab, vapourising the water and somehow miraculously not injuring either my lab partner or I despite us being just a few inches to the side watching close up that funky little whizzing ball and flame. The remaining thick glass beaker burned my fingers and thumb when I touched it.

    I was never totally sure why but I think dropping the second piece of sodium in combined with the now wet glass lid that possibly formed an air tight seal didn’t help…

  8. Mark

    One wonders what method would be used today to dispose of ten tons of reduced sodium.

  9. Ian

    Loved the dubbed in copy/pasta explosion audio. Nice touch there.

  10. Jess Tauber

    Actually sodium is on the right side of the Janet Left Step periodic table, developed in 1929 by a (then) elderly French polymath (see the second illustration at http://en.wikipedia.org/wiki/Alternative_periodic_tables).

    Our currently popular periodic table is a kluge, with inconsistent multiple graphical motivations, not helped by the fact that the system’s chemical behaviors are out of synch with with the quantum numbers behind it. Some of that can can be laid to interactions between electrons and relativity.

    Note that hydrogen, placed over the alkali metals, is NOT a metal- further it is just as happy being hydride ion, so could be also placed over the halides (which would parallel placement of helium, with an s2 electronic configuration that SHOULD merit placement above the alkaline earths, yet we like to put it with the p6 ‘noble’ gases).

    However, none of this changes the fact that fun will ensue when sodium hits water- I found that out the hard way one night in a chem lab cleaning unlabeled flasks that had dissolved anhydrous sodium in them, under the lab sink. I think it was when my entire lab coat sleeve was afire that I realized there was a problem and dropped the flask into the sink, so that now the entire sink was sending flames to the ceiling.

    After that, there were plenty of laughs to go around for everyone….

  11. Bigfoot
  12. Charlie

    They use liquid sodium as a coolant/heat transfer in the Fast Flux reactor at Hanford. That reactor was used to make Plutonium. I wonder if that sodium was from the original reactors used in the Manhattan Project?

  13. Chris

    If you thought sodium was a big explosion. You should look at what Cesium can do!
    To bad there isn’t enough Francium, that would be even bigger!

  14. Keith Hearn

    Lake Lenore is about 60 miles north of the Hanford Site. I was wondering if the sodium might be related to it. Not much else in that area that was related to war production.

  15. brett

    yep our teacher did that in high school too. I remember the sodium looking like a gray sausage that was in a rather long glass container,filled with oil. Every boy in that class suddenly had a revelation about the true potential of chemistry :-) and that it could possibly be FUN

  16. James

    The “marching band” music in the background really made the film :)

  17. John Baxter

    Lake Lanore is, aside from being about 60 mi N of Hanford is just north of Soap Lake. Coincidence? …

    It’s a rather interesting area geologically.

    Dab of sodium in balloon with kerosene. Flush. Unexplained sewer explosion (kept mild by not overdoing the Na) in the 1950s and likely other times in Cambridge, MA.

    (I did not participate or approve.)


  18. Mark

    MIT students have periodically dropped sodium in the Charles River. In 2007 this caused problems when some people cleaning trash out of the river encountered sodium residue. Several people were hurt and their boat damaged in the explosion.

  19. What about sodium used for aircraft engine discharge valve cooling? Once they discovered turbines, piston engines demand fell sharply. Just guessing… BTW, why not burn sodium in air rather than dumping it in the water?

  20. Wzrd1

    And today, it is renamed to Lake Draino.

  21. Mike

    The guys working on this disposal project wanted to be the salt of the Earth, but they fell a little short.

  22. Lime

    @chris The brainiac video was apparently faked, FYI.

  23. Georg

    They should have done that at night!
    We used to dispose Sodium and Potassium leftovers
    on lakes at nighttime.

  24. Naked Bunny with a Whip

    Everything I know about sodium, I learned from Mike and the ‘bots.

  25. Messier Tidy Upper

    @1. ragnar : “Why did they dispose of it that way? “

    Because, in Mythbusters spirit, its more fun! ūüėČ

    Who doesn’t like a good big explosion – provided no real harm is done – eh?

  26. Ganzy

    That Sodium disposal video is a classic!

    One of my favourite videos on the Alkali metals, is this old Open University demonsatration.

    The calm and orderly explanation of the narrator juxtaposed with the explosive chaos unleashed as the Cesium gets aquainted with H2O. Followed by the lab tech’s little whistle at the end cracks me up.

    “Let’s try cesium, our 5thÔĽŅ alkali metal.”

  27. Pseudolus

    Every chemistry teacher’s dream. My demos always shoot up to the ceiling, then as the drips fall, tiny little fireballs erupt on the bench.

  28. Jack

    How the world has changed. Today, we wouldn’t just dump sodium into a lake, even a dead lake. Actually, we’d go see for ourselves and find out that the lake isn’t actually completely dead. There are more industrial uses for sodium (aside from the obvious use of cleaning up halide spills. Definitely, we wouldn’t put it on a newsreel with canned music.

    Life was simpler then, and the producers didn’t have to worry about the audience questioning the appropriateness of what was being filmed or questioning the accuracy of the official story or the post-war propaganda angle.

  29. Brad

    Lake Lenore actually isn’t dead. It’s alkaline nature has made it a perfect place to introduce the Lahontan cutthroat trout for conservation. Growing up in Central Washington, I went fishing here a few times, but was never successful. Take a gander at http://www.washingtonlakes.com/FeaturedLake.aspx?id=562

  30. Gregosaurus

    @ 24. Naked Bunny with a Whip

    True. Anyone who saw The Horror of Party Beach already knew this.


  31. I had a chemistry professor in college who devised a (relatively) safe way of dropping nitrogen into water – he got a VERY large graduated cylinder, which he filled partially with water and then the rest of the way with kerosene. The sodium would go down into the water, release a bunch of hydrogen, and get carried up into the kerosene, where it would inertly fall back down. This would go on for the entire class.

    At the end of the semester he’d treat his students by just tossing sodium in the lake.

  32. Jonathan Ray

    It’s actually not that bad. The sodium will form NaOH, making the water very alkaline and killing a lot of the life in it, but over time the water will absorb CO2 from the atmosphere and precipitate carbonates until its pH returns to something reasonable and life can grow back. The problem here is that the lake may or may not be isolated from sources that could replenish its biodiversity. It would have been better to dump the sodium in the open ocean, spread out over a large area, where it will have negligible impact because the pH is more quickly neutralized and the life forms can easily grow back.

  33. ggremlin

    My 8th grade science teacher was a failed mad scientist.

    The sodium experiment burned three nice holes in the chalkboard, they’re still there 30 years later.
    Why don’t you desolve US currency(one dime only) in acid? You stink up the school and force an evacuation!
    Model hot air balloons and bunsen burners do not mix well, ask your local fire department.
    An introduction to what a Leyden jar does, by completing the circuit.

    I love science!

  34. Azrael

    “a tiny blue vertical flame followed it around” That would have been potassium most likely, sodium burns orange-yellow in the classic demonstration

  35. Mark

    When my father was a boy (a long, long time ago) he could buy all kinds of stuff from the local drug store. He kept a lot of it in a cabinet in the crawl space under our house when I was a boy. Every once in a while he would bring out the sodium, cut off a slice and throw it into the yard. Then we would spray it with water from the hose. Those were the days.

  36. oldebabe

    In high school I inadvertently blew up a couple of shelves playing around with Na, water, a test tube, and heat (the class was more impressed than the teacher…). Fun, but definitely, as you said, don’t try this at home.

  37. Since we’re all talking high school chemistry, my teacher demonstrated this with Potassium, rubbing alcohol, and a Barbie doll. (I still remember “Barbie Flamb√©” quite well. I understand that he made “G.I. Joe Flamb√©” as well.)

    My question… What was the Sodium used for during the war? Somehow, I can’t picture balloons filled to Sodium dropped from gliders into enemy lakes.

  38. Nigel Depledge

    Jess Tauber (10) said:

    Note that hydrogen, placed over the alkali metals, is NOT a metal

    Is, too.

    You just have to subject it to immense pressure to observe its metallic character, such as is found just above the core of Jupiter. Current theory has Jupiter’s immense magnetic field being generated by a layer of liquid metallic hydrogen at the base of the atmosphere.

    – further it is just as happy being hydride ion,

    Not “happy” as such. Hydride salts react violently with water too.

    What hydrogen is “happy” to do is exist as a cation (i.e. a proton, or, in aqueous solution, the hydroxonium ion). Otherwise, how do you explain the very rapid (diffusion-controlled) exchange of hydrogens atoms in water?

    Hydrogen has far more in common with the Group I metals than any other group of elements.

  39. Nigel Depledge

    Jess Tauber (10) said:

    . . . which would parallel placement of helium, with an s2 electronic configuration that SHOULD merit placement above the alkaline earths, yet we like to put it with the p6 ‚Äėnoble‚Äô gases . . .

    Wait, so you think Hemium should be placed according to its s2 electron configuration, but that hydrogen should NOT be placed according to its s1 electron configuration? In what universe is that logical?

    Besides, Helium is a noble gas, possessing a complete outer electron shell in its atomic form (which is pretty much the definition of a noble gas).

  40. Nigel Depledge

    High-school chemistry seemed a bit tame once I started doing chemistry as a part of my PhD.

    I once had an unexpected excess of phosphorus oxychloride, which caused a bit of an explosion, resulting in a cloud of HCl gas spreading across the ceiling of the lab. And the compound I had made being stuck to the ceiling of the lab.

    I’ve made Chromic Acid, which was a bit scary (I’ve never seen anything else dissolve stainless steel).

    I’ve used hydrofluoric acid, which was very scary indeed. Fortunately, nothing went wrong.

    I’ve used lithium aluminium hydride more times than I can remember. Lithal also reacts with water to release hydrogen gas, but not quite as vigorously as sodium metal.

    Oh, and I twice used lithium in tritiated water to generate radioactive hydrogen gas. It was boring, I should have used sodium. (The radioactive hydrogen was needed to radiolabel a compound I was using as an enzyme substrate, in a hydrogenation reaction done using a Raney Nickel catalyst, which was also fun* in its own way.)

    A fellow PhD student in the same lab got to use phosgene on a regular basis, and such entertaining things as silicon tetrachloride, which, when it reacts with water (and, oh boy, does it ever react with water!!) generates two products – HCl gas and glass.

    * By which I mean it spontaneously combusted in air.

  41. Nigel Depledge

    Ragnar (1) said:

    Why did they dispose of it that way? They could easily have added chlorine from the rather large chemical weapons stockpiles and made 20 tons of salt.

    Actually, this would have made 25.4 tons of salt.

    Relative atomic mass of sodium is 22.99 g/mol, whereas that of chlorine is 35.45 g/mol.

    Also there would have been the issue of containing the chlorine gas.

  42. Matthew Brewer

    I live just south of Lake Lenore. There’s a white ring of minerals around the lake. I wonder if this is a residue left over from this dumping? It’s pretty cool to see this happening in my backyard!

  43. K. Nilsson

    Wow… you were referenced in Today’s APOD. Great Job.
    For 28 Feb 2012

    Way to go Phil !!!
    (this is in reference to your Comet Gerrard post..somehow my reply ended up here)

  44. Nigel Depledge

    Matthewe Brewer (42) said:

    There’s a white ring of minerals around the lake. I wonder if this is a residue left over from this dumping?

    Unlikely. NaOH is highly soluble in water. What you see is probably some salts of magnesium or calcium.


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