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Basic Physics Heat Change Problem

  • #1

Homework Statement



How much heat is released freezing 75 grams of steam at 110 degrees celcius into ice at -5.1 degree celcius

Homework Equations






The Attempt at a Solution

I tried to do this problem but got an answer like -17101.6J. I don't need you guys to give me an answer but can you suggest how to setup a problem like this? I know Qlost+Qgained=0...so would the 2 phase changes (steam to liquid, liquid to solid) =0?
 

Answers and Replies

  • #2
Delphi51
Homework Helper
3,407
10
Several parts:
- cooling the steam
- condensing the steam to water
- cooling the water to freezing point
- freezing
- cooling the ice
 
  • #3
So would I have (Msteam*Lheatsteam)+(Mwater*Lheatwater)+(Mice*Lheatice)+(Mice*Sice+change in temp ice)=0?
 
  • #4
Delphi51
Homework Helper
3,407
10
(Mice*Sice+change in temp ice)=0?
Certainly not equal to zero - equal to the heat released that you are trying to find.

I don't know what "Sice" means. I would say
M*C*ΔT for each of the three coolings, where M is the mass, C the heat capacity per kg per degree and ΔT the change in temperature.
 
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