### Enthalpy of fusion

Posted:

**Sun Feb 11, 2018 11:45 pm**for problem 2 on the midterm, how would you find the delta H fusion of the ice cream?

Created by Dr. Laurence Lavelle

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

https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=130&t=27502

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Posted: **Sun Feb 11, 2018 11:45 pm**

for problem 2 on the midterm, how would you find the delta H fusion of the ice cream?

Posted: **Mon Feb 12, 2018 2:29 am**

You set it up as q=mcdeltaT + deltaH(fusion)(1/2m), which becomes deltaH(fusion)=((2)(q-mcdeltaT))/(m). Then you just plug in the numbers and you end up getting 3.7 kJ/g.

Posted: **Mon Feb 12, 2018 1:22 pm**

The total energy put into the ice cream is equal to the energy needed to raise the temperature from -2.8 to 0degC plus the energy needed to melt it ()

Posted: **Tue Feb 13, 2018 5:02 pm**

Can someone please explain the answer to this question in more detail? I don't understand why we use q=mcdeltaT + deltaH. Also, I plugged the values into this and got an incorrect answer.

Posted: **Wed Feb 14, 2018 5:07 pm**

We use the equation to find the q_{ice cream} because we have to account for the fact that it changes from solid (frozen) to liquid (melted). The accounts for the ice cream changing and then accounts for the phase change, where .