superheated water
2005-07-30 18:03:57.990022+00 by
Dan Lyke
4 comments
Whoah! Cool! You know that allegedly possible but never supposed to happen except under laboratory conditions thing where water superheated in a microwave can appear to not be boiling, but "explode" when something is put in it? I was just heating water to clean the conductive gel off of some EEG electrodes, grabbed it out of the microwave, lowered the probes into it and... whoosh! Would have sucked if it had burned me, but the quantity was low enough and the container was shaped such that it just bubbled to the top and over a bit, so it was really neat to see that science experiment in action.
[ related topics:
Dan's Life Cool Science
]
comments in ascending chronological order (reverse):
#Comment Re: made: 2005-07-31 07:39:28.607439+00 by:
whump
Back in Wisconsin, during sub zero winter nights, we'd superheat water in the microwave, rush it outside
and fling it into the air -- POOF -- instant snow!
#Comment Re: made: 2005-07-31 12:33:53.227052+00 by:
meuon
I'll also contend that the amount of ions and salts in the conductive gel is an ideal substance to do that to water.
And I've learned better than to ask why you were playing with EEG electrodes..
#Comment Re: made: 2005-07-31 22:49:27.20454+00 by:
petronius
I don't remember enough physics, but I do know that if you chill very still water down to below freezing, it needs some vibration to push it into the state change, ie, become solid. Is such an effect also seem in the state change from liquid to vapor?
#Comment Re: made: 2005-08-01 11:59:17.940034+00 by:
Dan Lyke
From the article (quoting another article): "the boiling is hindered by a lack of nucleation sites needed to form the bubbles". So, yeah, I think it's roughly the way you describe it.