Finding Specific Heat of Unknown Metal

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a1234
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Homework Statement



I'm asked to find the specific heat of Metal X in this simulation:
http://group.chem.iastate.edu/Greenbowe/sections/projectfolder/flashfiles/thermochem/heat_metal.html

Mass of Metal X = 120 g
Temp of Metal X = 220 degrees
Mass of Water = 30 g
Initial Temp of Water = 20 degrees
Final Temp of Water = 85.6 degrees
Specific Heat of Water = 4.186 J/gram C

Homework Equations



ΔQ = mCpΔT is the equation for finding the heat needed to change the temperature.

The Attempt at a Solution



Qwater = mwater*cpwater*change in temperature
Qwater = 30*4.186*65.6
Qwater = 8238.048 J

I think the Q of the metal would be -8238.048 J. I'm not sure what to do from there.
 
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a1234 said:
I think the Q of the metal would be -8238.048 J. I'm not sure what to do from there.

It's been a while since I've done this, so someone please correct me if I am mistaken... So you have the initial heat of your metal as ##8.24 kJ##. Specific heat capacity is measured in terms of ##\frac{J}{g⋅K}##. A total of ##8.24 kJ## of energy was transferred using ##120 g## of metal, at ##493 K##. Can you think of a quantity to describe the heat that can be transferred from this metal for any given mass and temperature?
 
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Is it 0.51?
I did these calculations after getting the Q for the metal:
Cpmetal = Q/(m*change in temp)
Cpmetal = -8238.048/(120*-134.4)
Cpmetal = 0.51
 
a1234 said:
Cpmetal = Q/(m*change in temp)
Cpmetal = -8238.048/(120*-134.4)
Cpmetal = 0.51

That looks correct to me. You should also add in your units.