Calculating Specific Heat of a Tin Sample: A Quick Question and Solution

[Aikenfan]

I saw this problem online...

A 250 gram piece of tin at 99 degrees C. is dropped into 100 grams of water at 10 degress C. If the final temperature is 20 degrees C., calculate the specific heat of the tin sample. Be sure to include the appropriate units !
Note c for water = 4.186 KJ/kg.K

Solution 41766

Assume K = 273.15 + C where K is Kelvin and C is Celsius.
Hints:
Let the specific heat of tin be x kJ/(kg*K).
0.250 * x * (372.15 - 293.15) = 0.100 * 4.186 * (293.15 - 283.15)
Solve for x.

and i just wondered...where did the (372.15 - 293.15) come from? thank you very much!

 

[denverdoc]

what are the 3 temps after converting to Kelvin?

then heat lost by tin=heat rise of water

 

[Aikenfan]

99--- - 174.15
10---- -263.15
20---- -253.15

 

[denverdoc]

you sure, k=273.15+C