There was this problem regarding Latent Heat that I would like further clarification: Problem: 200g of ice at -10C is added to 1kg of water at 15C in an insulated container. Is there enough ice to cool the water to 0C? If so, how much ice and water are present once equilibrium is reached? In the book it demonstrated the solution by finding the Energy required to melt all 200g of ice Q1: Q1 = mc(dT) + mL = 70.9kJ -- I understand that. Then it says "Cooling the water to 0C extracts an ammount of heat given by Q2": Q2 = mc(dT) = 1kg(4.184kJ/kg*K)(15K) = 63kJ. -- Why did they set initial Temperature to be 0C?