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Author Topic: Why do metals melt, but not, for example, wood?  (Read 15459 times)

Offline Chemistry4me

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Why do metals melt, but not, for example, wood?
« Reply #25 on: 21/01/2009 10:31:18 »
So where does that get us to?
 

Offline dentstudent

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Why do metals melt, but not, for example, wood?
« Reply #26 on: 21/01/2009 10:43:14 »
I guess that it means that in atmospheric presures, carbon stays in its solid state up to around 4000C, after which it sublimates. I can't think that there would be too many domestic bonfires which would get up to those temperatures!
 

Offline Chemistry4me

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Why do metals melt, but not, for example, wood?
« Reply #27 on: 21/01/2009 11:05:41 »
I think Madidus_Scientia has fallen asleep
 

Offline dentstudent

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Why do metals melt, but not, for example, wood?
« Reply #28 on: 21/01/2009 11:13:23 »
I think Madidus_Scientia has fallen asleep

That used to happen during chemistry lessons to me too.
 

Offline Chemistry4me

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Why do metals melt, but not, for example, wood?
« Reply #29 on: 21/01/2009 11:23:09 »
Haha, me too!
 

Offline lightarrow

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Why do metals melt, but not, for example, wood?
« Reply #30 on: 21/01/2009 13:14:21 »
Even in the absence of oxygen, wood decomposes at high temperatures into hydrocarbons, methyl alcohol, acetone and other volatile substances (it's for this reason that wood burns making flames); as sophiecentaur said, it doesn't stays wood anylonger and it becomes charcoal. At still higher temperatures charcoal decomposes again losing (essentially) hydrocarbons and becoming almost pure carbon; then at ~ 4000C it sublimates, as already said.

One of the first laboratory experiences we made at school was "wood distillation". The product is essentially methyl alcohol (which old name is infact "wood spirits" or "wood alcohol"  for this reason).
« Last Edit: 21/01/2009 13:21:57 by lightarrow »
 

The Naked Scientists Forum

Why do metals melt, but not, for example, wood?
« Reply #30 on: 21/01/2009 13:14:21 »

 

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