deadrush
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What does "fusion" mean in a chemistry procedure / book
In the link below it mentions "fused zinc chloride". What exactly does that mean? Ive read about the procedure for home-made kmno4 and usually there
is a step fusing naoh and mno2 i believe (been a long time). With 2 compounds i intuited the meaning to be mix solids excessively in a mortar and
pestle then add heat. How does one fuse a single compound?
https://books.google.com/books?id=2BNIAAAAIAAJ&newbks=1&...
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chornedsnorkack
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"Fusion" means "melting". So NaOH and MnO2 need to be heated to the point where one of them melts. A single compound - again, heat it to melting. I
understand that it does not have to be "molten" when used - when it is "fused" not "molten", it has been melted and allowed to cool down and freeze or
congeal again.
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Dr.Bob
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For some compounds this might just dry them well, like ZnCl2. At their MP, there will be little H2O left. For some reactions, a fusion just
creates a molten salt bath to act as the solvent. But fusion and melting are similar concepts. Or you could put your ZnCl2 in an atomic bomb and
try to do fusion... That might be harder, but certain little water left there also.
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j_sum1
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Just to add to the ambiguity...
In thermodynamics, latent heat of fusion refers to solidification/ freezing.
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chornedsnorkack
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Quote: Originally posted by j_sum1  | Just to add to the ambiguity...
In thermodynamics, latent heat of fusion refers to solidification/ freezing. |
Melting and freezing are reverse processes and have identical latent heat, except for sign. Are you sure there is any ambiguity here?
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j_sum1
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True.
It was a bit of a joke among my friends at university that half the job was working out the quantity and the other half was working out the sign.
So yes. Latent heat of fusion equsls -1 x latent heat of melting.
But the phrase used is fusion. Which afaiu refers to solidification. Context tells you whether to use a positive or negative number.
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