From: utzoo!dciem!mmt
Newsgroups: net.misc
Title: Re: "Re: Cosmos A-Bomb"
Article-I.D.: dciem.155
Posted: Mon Jan 24 11:04:24 1983
Received: Mon Jan 24 12:02:21 1983
References: alice.1415

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From: utzoo!decvax!harpo!eagle!mhtsa!alice!sjb
Dropping alkali metals into water should not be taken so lightly.
A couple years ago around here, a couple kids stole 1 or 2 pounds
of potassium from the chemistry lab in school and threw it into
a local creek while still in the jar (with lid open though) --
the resultant explosion killed both of them.
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It's not surprising that the explosion killed the kids if they
were still in the jar.

But seriously, folks, this alkali metals in water business should indeed
not be treated lightly. When I was a kid, my father usually celebrated
the visits of a special but rarely seen friend with what he called
"The sodium ceremony". The two of them would don cloaks and other
mysterioso gear, prepare a bucket full of warm water and soak
the lawn with water. They would take what memory says must have
been about 100g of metallic sodium, wrap it with a sheet of
potassium, and throw it in the bucket, ensuring everyone else
was WELL clear. At first, nothing would happen, then there would
be the purple potassium glow (I guess the delay was because both
the potassium and the sodium were kept under oil). The ball would
skitter around, popping a bit, on the water, with at first the
purple flame and then the yellow sodium flame. After an indeterminate
time, the whole thing would explode in a big sodium-yellow flare,
sending bits all over the lawn (maybe a 10-meter diameter), where
they sparkled as they hit the wet grass. Afterwards, the lawn
was thoroughly soaked, and there were always more unexploded bits
of sodium to sparkle. It never seemed to do the grass any harm, though.
(I should have added that the ceremony was always at night,
preferably moonless, and all the house lights were turned out.)

I hate to think what 1 kilo of potassium in a jar would do.
A kilo unconfined would probably do no more harm than a pile
of gunpowder. Potassium is so reactive that it seems to have
a sort of Leidenfrost (?) effect, keeping a shell of (?) steam
between itself and the water. Sodium, on the other hand, goes BANG.
In the ceremony, I think the potassium wrapping served to heat
the sodium before the water got to it.

		Martin Taylor