## Homework Problem 4C.13

105311039
Posts: 107
Joined: Fri Aug 02, 2019 12:16 am

### Homework Problem 4C.13

For this question, I am confused on why you add the the energy to melt the ice into the MCAT equation? I've never seen a question use this concept and just confused on it.

KnarGeghamyan1B
Posts: 102
Joined: Fri Aug 09, 2019 12:15 am

### Re: Homework Problem 4C.13

To go from 0 degrees ice to 45 degrees liquid water, we must first go from 0 degrees ice to 0 degrees liquid water, which required an enthalpy of formation calculation. We can then use mCdeltaT to find the heat necessary to go from liquid water at 0 to the final temperature.

CalvinTNguyen2D
Posts: 102
Joined: Thu Jul 25, 2019 12:16 am

### Re: Homework Problem 4C.13

The problem asks for us to convert 0 degrees C ice into 45 degrees water. However, to do this, we need to melt the ice into water, which requires us to use the enthalpy of formation and a phase shift calculation. After that, we can calculate the energy required to heat 0 degrees water to 45 degrees water without further issue.

205154661_Dis2J
Posts: 109
Joined: Wed Sep 18, 2019 12:21 am

### Re: Homework Problem 4C.13

It is very helpful to draw the graph. We see that in order to melt ice, we need to go through the plateau on the heating curve that turns a solid into liquid. So we have to include that in our calculations .