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Topic: melting point?  (Read 3263 times)

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Offline ProblemSets

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melting point?
« on: April 05, 2007, 07:58:03 AM »
Which structure will have the highest melting point?

i believe B and C are dipole-dipole forces, which are stronger than A and D which are london disperion forces. i know dipole-diople is stronger than london. Would the answer be C since it has the longest carbon chain that is polar.

thanks

Offline Yggdrasil

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Re: melting point?
« Reply #1 on: April 05, 2007, 11:26:46 AM »
Why would you say that B anc C are polar?  The electronegativity difference between C and H isn't enough to make C-H bonds be polar to any extent, not to mention that the geometries won't make them polar either.

So, given that the dominant intermolecular force for all four compounds is dispersion forces, what would you say the highest melting compound is?

Offline ProblemSets

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Re: melting point?
« Reply #2 on: April 05, 2007, 11:36:14 AM »
i change my answer to A

Offline Yggdrasil

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Re: melting point?
« Reply #3 on: April 05, 2007, 11:41:49 AM »
You know the answer, but the important question is whether you know the reason why.

Offline ProblemSets

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Re: melting point?
« Reply #4 on: April 05, 2007, 11:44:44 AM »
yes, i understand now. thank you.

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