A 0.25kg iron block at 500K is quickly placed in an insulated container holding 0.50kg of water at 300K. The specific heat capacities are ciron=450Jkg−1K−1 and cwater=4180Jkg−1K−1. Neglecting any energy exchange with the container or surroundings, calculate the equilibrium temperature of the iron–water system.
a) 319K
b) 310K
c) 335K
d) 303K