Dencology

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.Question 152 ochem in destroyer contradicts Kaplan (page 286) about melting and boiling point. .

.How come?.



branching decreases MP and BP. but destroyer says that symmetry is the main thing to consider when it comes to MP. but according to Kaplan, if the branching inc. then mp and bp will decrease as well. but if the chain length inc. then both of them would inc.



so what is the deal?
 

Danny289

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.Question 152 ochem in destroyer contradicts Kaplan (page 286) about melting and boiling point. .

.How come?.



branching decreases MP and BP. but destroyer says that symmetry is the main thing to consider when it comes to MP. but according to Kaplan, if the branching inc. then mp and bp will decrease as well. but if the chain length inc. then both of them would inc.



so what is the deal?
go with destroyer, the point is Symmetry for MP. the Destroyer explanation is enough.
 

zuma35

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I don't have the Destroyer in front of me, so I don't have the exact question. Basically, branching decreases both melting and boiling point. What Destroyer means is that if and only if a molecule has perfect symmetry, like in neopentane, the melting point would increase.
 
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