Hot water at 90 degrees C is poured into a large Styrofoam cup that contains water at 20 degrees C. The final temperature of the mixture is 75 degrees C, closer to the initial temperature of the hot water.
A) which mass of water was the greatest, the hot or the cold water? Does that mean that the heat lost by hot water is less than the heat gained by the cold water? Explain.
B) calculate the ratio of cold water to hot that would give this result. Start with energy conservation: Q(H) + Q(C) = 0
C) If there were 150g of hot water, calculate how much heat was exchanged.