## Practice Midterm #7

$\Delta U=q+w$

104969854
Posts: 36
Joined: Fri Sep 29, 2017 7:05 am

### Practice Midterm #7

Will someone share how they did #7 on the practice midterm?

I'm using the law Qsys= -Qsurr, translating that to Qice= -Qwater and MCAT= -MCAT, and I keep getting 26 degrees Celsuis. What am I doing wrong here?

Angela 1K
Posts: 80
Joined: Fri Sep 29, 2017 7:05 am

### Re: Practice Midterm #7

Make sure you account for the phase change of the ice to liquid in your qice

mayapartha_1D
Posts: 50
Joined: Fri Sep 29, 2017 7:07 am

### Re: Practice Midterm #7

Hi!

Yes, make sure you add the enthalpy for melting the ice (the phase change) for the Q of the system. That should get you the right answer!