# Chemistry

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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)

• Chemistry - ,

[mass alloy x specific heat alloy x (Tfinal-Tinitial)] + [(calorimeter constant x (Tfinal-Tinitial)] = 0

• Chemistry - ,

(30.5)(X)(10.8)+(?)(10.8)=0

What number goes in the calorimeter constant ?

• Chemistry - ,

9.2 J/K = heat capacity of the coffee cup.

• Chemistry - ,

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.

• Chemistry - ,

I didn't include the water and should have done so.
(mass water x specific heat water x (Tfinal-Tinitial)) + (mass alloy x specific heat alloy x (Tfinal-Tinitial)) + Ccal(Tfinal-Tinitial) = 0

• Chemistry - ,

so, what is the t final- t initial for ccal?