Re: OFF: Chemical processes for underwater fire

On Wed, 5 Jan 2000, Paul&Kathy wrote:

>Pat, for chemicals that combust in contact with water, go to:
>http://www.scescape.net/%7Ewoods/elements.html
>and dig around the light-blue ones towards the left of the table.
>The page isn't perfect, but it's a sufficient starting point.
>
>The most interesting option IMO is Sodium (Na), as in NaCl, aka
>common Salt, which is available in abundance in seawater.
Problem with sodium, and all other Leftist elements ;) is that they
don't exist as elements in nature.  If you take any of these metals
(in pure form) and dump them in water you end up with metal hydroxide
(a strong base) and hydrogen gas.  Cesium literally explodes in water:
the metal reacts so violently with the water that it rapidly forms the
hydroxide, and the heat of the reaction ignites the hydrogen gas
that's evolved. Pretty neat, but don't try it at home.

Sodium isn't quite as reactive, but the end results are the same.

>
>If we're still on octopi (or other sealife), I'm thinking about a bodily
>process that makes a Sodium compound from the surrounding
>water.  The compound is perfectly safe in vivo, but breaks down
>fairly rapidly in seawater to allow the Sodium in pure form to get to
>work.  I dunno enuf about the chemistry (and biochemistry, but
>that's more kinda open-ended I guess) to give a much more
>detailed view than that, I'm afraid, but it sounds feasable to me.
It would certainly be possible to make a sodium compound from salt
water, if you have something to exchange for the sodium. But you're
not going to get sodium in metalic form easily.

>
>This has a practical evolutionary advantage as a defensive
>mechanism, and could become a useful tool.
Yes indeed. Cornered octopi can shoot streams of sodium metal at the
eyes and noses of attacking aquatic life, which turns to NaOH and
burns the insides of their noses and eyes. ACK!

>
>---
>Pb, who is (at last) back to a "real" email prog again, as promised.
>(Also, wondering what happened to the Proverbs of Bastet relay)
>
Sally's apparently away for the time being, but it all ended up
somewhere in her pages as well as mass mailings here.  Try starting at
frontiernet.net/~scaves (I think that's right, anyway).

Padraic.