November 28, 2024, 03:37:48 AM
Forum Rules: Read This Before Posting


Topic: molar heat  (Read 5149 times)

0 Members and 1 Guest are viewing this topic.

dathrilla

  • Guest
molar heat
« on: June 07, 2006, 03:59:23 PM »
Hi,

1 gram of C6H6 releases 10 kcal

What is the molar heat in the formation of C6H6?

The proposed answer is 11.9 kcal, can someone tell me how ypu can possibly attain this answer?

Offline Albert

  • Lonely Wanderer
  • Retired Staff
  • Sr. Member
  • *
  • Posts: 1050
  • Mole Snacks: +112/-22
  • Gender: Male
  • Half Decent Pharmaceutical Chemist
Re: molar heat
« Reply #1 on: June 07, 2006, 04:18:34 PM »
Can you post the text of the problem? I think there's something wrong in what you wrote: 1 gram of benzene can't release 10 kcal, according to my calculations.

dathrilla

  • Guest
Re: molar heat
« Reply #2 on: June 07, 2006, 04:27:25 PM »
oh ok, sorry i'm studying abroad and it's in french...

t1 gram of benzene releases while burning 10 kcal

Calculate the molar heat...

Does that sound right?

Thanks Albert

dathrilla

  • Guest
Re: molar heat
« Reply #3 on: June 07, 2006, 04:53:24 PM »
Albert?

dathrilla

  • Guest
Re: molar heat
« Reply #4 on: June 07, 2006, 05:49:37 PM »
?
?

Offline Albert

  • Lonely Wanderer
  • Retired Staff
  • Sr. Member
  • *
  • Posts: 1050
  • Mole Snacks: +112/-22
  • Gender: Male
  • Half Decent Pharmaceutical Chemist
Re: molar heat
« Reply #5 on: June 07, 2006, 06:06:57 PM »
Here I am. Hey, dude, remember that I also have a life!  :)

First of all you need to write the balanced chemical equation describing the combustion of a mole of benzene.
Then, calculate the deltaH of combution (or reaction) of benzene: 10 Kcal/moles of benzene in 1g

In the end, check out the deltaH of formation of the products of combustion and calculate the deltaH of benzene.

Sponsored Links