Question

How much heat is lost from a block of solid gold when 2000 g of this gold (Au) cools from 1064 degrees C to 25 degrees C? (Cp(Au) = 0.128 J/g*degC)

Answer 1

I got `265,984J` lost by our gold.

Explanation:

Here I would use the general expression of heat `Q` exchanged by a mass `m` to go from an initial temperature `T_i` to a final temperature `T_f`:
`Q=mc_p(T_f-T_i)`
In your case:
`Q=2000*0.128(25-1064)=-265,984J`
The negative sign will give us heat "going out" from our system or our system's internal energy being reduced.