A10.0 gram piece of metal is placed in an insulated calorimeter containing 250.0 g of water initially at 20.0°c. if the final temperature of the mixture is 25.0°c, what is the heat change of water?

a) 5230 j
b) −5230 j
c) 209 j
d) −209 j
e) 5440 j

The heat change of water is calculated through the equation,
                                H = m(cp)dT
where H is heat, m is mass, cp is the specific heat, and dT is the change is temperature. Substituting the known values,
                               H = (250 g)(4.18 J/g°C)(25°C - 20°C) = 5255 J
The nearest value to this is letter A. 5230 J. 

Elias is almost correct. he just got it backwards.the correct answer is that it demonstrates elastic potential energy transforming into kinetic energy.