### 4C.3

Posted:

**Mon Jan 27, 2020 8:57 pm**This question has 2 parts but the answer key only gives one answer. What did you guys get for these parts?

Created by Dr. Laurence Lavelle

https://lavelle.chem.ucla.edu/forum/

https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=76&t=57536

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Posted: **Mon Jan 27, 2020 8:57 pm**

This question has 2 parts but the answer key only gives one answer. What did you guys get for these parts?

Posted: **Mon Jan 27, 2020 9:34 pm**

For part a, I believe it's 343K for the final temperature and 935.1J for the change in enthalpy, and part b it's 374K for the final temperature and 947.6J for the change in enthalpy.

Posted: **Tue Jan 28, 2020 12:27 pm**

For part B how do we calculate the change in enthalpy? It is not included in the answer key

Posted: **Thu Jan 30, 2020 1:46 am**

Sara Richmond 2K wrote:For part B how do we calculate the change in enthalpy? It is not included in the answer key

The steps I followed were almost exactly the same as the ones shown n example 4C.1 on page 266 in the book. This explains how to find both the final temperature and the change in enthalpy.

Posted: **Sat Feb 01, 2020 4:05 pm**

Eileen Si 1G wrote:For part a, I believe it's 343K for the final temperature and 935.1J for the change in enthalpy, and part b it's 374K for the final temperature and 947.6J for the change in enthalpy.

Wouldn't the change in enthalpy just be 765J because in example 4C.1 on page 266, the solution states that "the enthalpy change at constant pressure is equal t the heat supplied," so deltaH = qp

Also, I'm getting 1275J for part (b), I'm doing deltaH = 765 + (0.82 * 8.3145 * 74.813) = 1275J