Two 20.0g ice cubes at -10.0 C are placed into 275g of water at 25.0 C. Assuming no energy is transferred to or from the surroundings, calculate the final temperature of the water after all the ice melts.

Answer 1

heat to melt ice cube 1 + heat t melt ice cube 2 + heat to raise T ice melted ice cubes from zero to final T + heat lost by 275 g H2O = 0.

heat to melt ice cube 1 = mass x heat fusion.
heat t melt ice cube 2 = mass x heat fusion.
heat to raise water from 20 g ice cubes from zero to final T = mass x specific heat x (Tfinal-Tintial)
heat lost by 275 g water = mass water x specific heat water x (Tfinal-Tintial) = zero. Solve for Tfinal. I something a little less than 20 C.