Physical Chemistry Question (work done during decomposition)

  • Thread starter Paint
  • Start date
  • #1
1
0

Homework Statement



A sample consisting of 1.0 mol of calcium carbonate CaCO3(s) was heated to
800°C, when it decomposed (CaCO3 → CaO + CO2). The heating was carried out in a
container fitted with a piston which was initially resting on the solid. Calculate the work
done during complete decomposition at 1.0 atm. What work would be done if instead of
having a piston the container was open to the atmosphere?

Homework Equations



Expansion work against constant external pressure:

w=-pex[tex]\Delta[/tex]V

The Attempt at a Solution


Ok the textbook gives an example, so I tried following that. Because Vf>>Vi, and Vf=nRT/pex, then w=-pex x nRT/pex=-nRT (im assuming n is number of moles of CO2?). 1 mole of CaCO3 makes 1 mole of CO2, so plugging in numbers, I get 8.9kJ, although I dont use the 1 atm pressure at all, so I'm thinking I'm doing the second part of the question first. Any help would be appreciated.
 

Answers and Replies

Related Threads on Physical Chemistry Question (work done during decomposition)

  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
1
Views
2K
  • Last Post
2
Replies
29
Views
3K
  • Last Post
Replies
1
Views
3K
  • Last Post
Replies
2
Views
793
Replies
2
Views
31K
Replies
2
Views
3K
  • Last Post
Replies
1
Views
3K
  • Last Post
Replies
0
Views
1K
  • Last Post
Replies
1
Views
2K
Top