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bcjochim07
May10-08, 09:12 PM
1. The problem statement, all variables and given/known data
Your 300 mL cup of coffee is too hot to drink when served at 90 degrees C. What is the mass of an ice cube, taken from a -20 degree C freezer, that will cool your coffee to 60 degrees C?


2. Relevant equations



3. The attempt at a solution

I'm pretty sure I can do this problem, but the only thing I am unsure of is what the specific heat of the coffee is. Should I assume that is the same as that of liquid water? Thanks

mgb_phys
May10-08, 09:26 PM
Yes - there isn't much coffee in coffee and adding small amounts of solutes doesn't change the specific heat much, it does have a large effecton freezing/boiling points.

Remember to include the latent heat of the ice melting as well as the specific heat of ice heating upto 0!