A 10.0 g sample of pure gold (Au) at 55.0 C gives off 45.0 J of heat to its surroundings. The specific heat capacity (C) of Au is 0.129J/g*C. What is the final temperature, in C, of the Au sample?
The equation you're going to want to use here is:
In this equation, the parameters are defined as follows:
Now rearrange the equation to solve for final temperature...
And simply plug in your given parameters from the problem. Note that
Cancel units, if it's easier to think of that way.
Do the math...