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Topic: Cracking  (Read 3727 times)

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yeung

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Cracking
« on: August 25, 2005, 03:06:59 AM »
After cracking, propene and heptane are obtained.How can we use fractional distillation to separate them as they are gases?

Offline xiankai

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Re:Cracking
« Reply #1 on: August 25, 2005, 03:11:58 AM »
propene has a lower boiling point than heptane because it contains less atoms. hence most of it would distilled first before heptane.

i suppose u know the basic principles of fractional distillation.
one learns best by teaching

Offline FeLiXe

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Re:Cracking
« Reply #2 on: August 25, 2005, 04:37:42 AM »
just cool them down. at 98°C heptane will condense. propene needs a lower temperatue.
« Last Edit: August 25, 2005, 04:50:28 AM by FeLiXe »
Math and alcohol don't mix, so... please, don't drink and derive!

Offline Donaldson Tan

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Re:Cracking
« Reply #3 on: August 25, 2005, 03:50:08 PM »
propene boils at -47.8C at 1atm.

heptane boils at 98C at 1atm.

 ;)
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