Using PV=nRT to solve for internal energy

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Kelsey Ouyang 3H
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Joined: Fri Sep 25, 2015 3:00 am

Using PV=nRT to solve for internal energy

Postby Kelsey Ouyang 3H » Wed Jan 20, 2016 5:26 pm

For 8.49, 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 given that delta H =-318 kJ.

In this question, I know that we will be using PV=nRT to find work, which is needed to find internal energy. Isn't the equation PV=nRT only used if the gas is ideal. In the question, there is no reference to whether this reaction involves ideal gases. Therefore, how was I supposed to know that we are looking at ideal gases which would allow me to use the ideal gas law to convert PV to nRT which will help me find the work needed, which helps me find internal energy?

304621080
Posts: 20
Joined: Fri Sep 25, 2015 3:00 am

Re: Using PV=nRT to solve for internal energy

Postby 304621080 » Wed Jan 20, 2016 8:59 pm

Although the problem does not explicitly tell you it is an ideal gas; however, the key hint is that you are given moles which hints that you have to exchange P(Delta)V to (Delta)nPT in finding the change in internal energy.


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