Chemical Forums

Chemistry Forums for Students => High School Chemistry Forum => Topic started by: yeung on August 25, 2005, 03:06:59 AM

Title: Cracking
Post by: yeung 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?

Title: Re:Cracking
Post by: xiankai 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.

Title: Re:Cracking
Post by: FeLiXe on August 25, 2005, 04:37:42 AM

just cool them down. at 98°C heptane will condense. propene needs a lower temperatue.

Title: Re:Cracking
Post by: Donaldson Tan on August 25, 2005, 03:50:08 PM

propene boils at -47.8C at 1atm.

heptane boils at 98C at 1atm.

 ;)