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### When to use Cv or Cp? to calculate change in Entropy

Posted: Sun Mar 19, 2017 11:20 am
I understand that we use Cv or Cp when the it states that its either at constant volume or pressure? But if these words are not used, and it just states that its a monatomic ideal gas, which C do use? I noticed that we normally use Cv but why?

### Re: When to use Cv or Cp? to calculate change in Entropy

Posted: Sun Mar 19, 2017 11:34 am
When we use Cv, it is usually used when there is a change in temperature in the problem

### Re: When to use Cv or Cp? to calculate change in Entropy

Posted: Sat Jan 20, 2018 12:09 pm
It depends on the type of system the reaction is being carried out in. If the problem specifies that it is isothermal, use Cp. It it is being carried out in isochoric, use Cv. If it is isobaric, use Cp to calculate q because pressure is not changing and change in volume will be accounted for in calculating w.

### Re: When to use Cv or Cp? to calculate change in Entropy

Posted: Tue Jan 23, 2018 4:38 pm
Maria Bajenov 1I wrote:It depends on the type of system the reaction is being carried out in. If the problem specifies that it is isothermal, use Cp. It it is being carried out in isochoric, use Cv. If it is isobaric, use Cp to calculate q because pressure is not changing and change in volume will be accounted for in calculating w.

In the isobaric case, how would one find q?