Chemistry
posted by Nevaeh on .
A 30.5 g sample of an alloy at 94.0°C is placed into 48.7 g water at 20.3°C in an insulated coffee cup. The heat capacity of the coffee cup (without the water) is 9.2 J/K. If the final temperature of the system is 31.1°C, what is the specific heat capacity of the alloy? (c of water is 4.184 J/g×K)

[mass alloy x specific heat alloy x (TfinalTinitial)] + [(calorimeter constant x (TfinalTinitial)] = 0

(30.5)(X)(10.8)+(?)(10.8)=0
What number goes in the calorimeter constant ? 
9.2 J/K = heat capacity of the coffee cup.

It's still not giving me the right answer. I'm pulling in the numbers, and doing the equation right. But, it keeps telling me, I am wrong.

I didn't include the water and should have done so.
(mass water x specific heat water x (TfinalTinitial)) + (mass alloy x specific heat alloy x (TfinalTinitial)) + Ccal(TfinalTinitial) = 0 
so, what is the t final t initial for ccal?