December 22, 2024, 04:57:30 PM
Forum Rules: Read This Before Posting


« previous next »
Pages: [1]   Go Down

Topic: Cracking  (Read 3977 times)

0 Members and 1 Guest are viewing this topic.

yeung

  • Guest
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?
Logged

Offline xiankai

  • Chemist
  • Full Member
  • *
  • Posts: 785
  • Mole Snacks: +77/-37
  • Gender: Male
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.
Logged
one learns best by teaching

Offline FeLiXe

  • Theoretical Biochemist
  • Chemist
  • Full Member
  • *
  • Posts: 462
  • Mole Snacks: +34/-7
  • Gender: Male
  • Excited?
    • Chemical Quantum Images
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 »
Logged
Math and alcohol don't mix, so... please, don't drink and derive!

Offline Donaldson Tan

  • Editor, New Asia Republic
  • Retired Staff
  • Sr. Member
  • *
  • Posts: 3177
  • Mole Snacks: +261/-13
  • Gender: Male
    • New Asia Republic
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.

 ;)
Logged
"Say you're in a [chemical] plant and there's a snake on the floor. What are you going to do? Call a consultant? Get a meeting together to talk about which color is the snake? Employees should do one thing: walk over there and you step on the friggin� snake." - Jean-Pierre Garnier, CEO of Glaxosmithkline, June 2006
Pages: [1]   Go Up
« previous next »
Sponsored Links