MadSci Network: Chemistry |
Well Michael, The cracking is due to the water in the salt boiling and producing [steam - D.B.] at that temperature, the same happens when you put bacon in a frying pan. The jumping could be the gas pushing the salt around. My lab partner "Bunsen" Hamilton has done your experiment and got the temperature up to about 350C before she burnt her hand (better wear gloves the next time!) but you could get it up to about 800C before the salt melts - then you get a orange flame from the sodium in table salt. Don't go above 1000C 'cause the spoon melts then ! Hope this helps. Peter "beaker" Traill Dan Berger adds: Above 800C or so, water will decompose into hydrogen and oxygen, so you would get all sorts of interesting effects.
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