September 20, 2019, 02:31:27 PM
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Topic: cis-trans  (Read 3561 times)

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Offline vhpk

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cis-trans
« on: June 08, 2007, 08:58:20 PM »
with a compound, whether cis-compound or trans compound has a higher boiling point and melting point
Genius is a long patience

Offline chunkmartinez

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Re: cis-trans
« Reply #1 on: June 08, 2007, 09:22:58 PM »
cis has a higher boiling point
trans has a higher melting point

Offline vhpk

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Re: cis-trans
« Reply #2 on: June 08, 2007, 11:55:59 PM »
I want to know the reason, can u explain for more details ;D
Genius is a long patience

Offline chunkmartinez

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Re: cis-trans
« Reply #3 on: June 09, 2007, 05:02:18 PM »
cis's boiling point will be higher because it is polar, and carries both dispersion forces, as well as dipole-dipole interactions. Where as the trans isomer is non-polar, having only dispersion forces.

Offline Yggdrasil

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Re: cis-trans
« Reply #4 on: June 09, 2007, 05:30:29 PM »
The melting point of cis-alkenes is elevated compared to trans-alkenes because the sterics of cis-alkenes are not as favorable to close packing in solids.  So despite having slightly greater intermolecular forces, cis-alkenes melt at a lower temperature than trans-alkenes.

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