Homework 8.49 question

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Shreya Narain 2J
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Joined: Fri Sep 25, 2015 3:00 am

Homework 8.49 question

Postby Shreya Narain 2J » Sun Jan 17, 2016 8:48 pm

Oxygen difluoride is a colorless, very poisonous gas that reacts rapidly with water vapor to produce O2, HF, and heat: What is the change in internal energy for the reaction of 1.00 mol OF2.


For this question, I know that and the heat released is 318kJ, how exactly do I find the work? I also know that but what exactly do with that?

KVu 3G
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Joined: Fri Sep 25, 2015 3:00 am

Re: Homework 8.49 question

Postby KVu 3G » Sun Jan 17, 2016 11:18 pm

You find w using w=-P * delta V which can be derived from the ideal gas equation.

PV=nRT



Substitute for gives you .

New equation is where q is given, R is a constant, T=298K, and =1 mol
Please correct me if I've made any mistakes, hope it helped.

Aaron Knuteson 3K
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Joined: Fri Sep 25, 2015 3:00 am

Re: Homework 8.49 question

Postby Aaron Knuteson 3K » Mon Jan 18, 2016 4:32 pm

This may be a dumb question, but where is the 298K coming from?

Thanks!

Joshua Kim 3H
Posts: 21
Joined: Fri Sep 25, 2015 3:00 am

Re: Homework 8.49 question

Postby Joshua Kim 3H » Mon Jan 18, 2016 10:54 pm

I believe the 298K comes from assuming that the temperature was at the standard state of usually 25 deg. Celsius making 273+25=298K


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