4A.7

[Chris Tai 1B]

(a) Calculate the heat that must be supplied to a copper kettle of mass 400.0 g containing 300.0 g of water to raise its temperature from 20.0 8C to the boiling point of water, 100.0 8C. (b) What percentage of the heat is used to raise the temperature of the water?

Could someone help me walk through part a of this question? I'm a bit confused as to how to deal with the multiple specific heats of water and copper, do you just add them together?

[Alicia Lin 2F]

Yes, you set up 2 equations: one for changing the temperature of copper and one for changing the temperature of water. Solve for heat and add these two together to get the total heat required.

[Tyler Angtuaco 1G]

Yes, just add the heat supplied to the copper kettle and the heat supplied to the water to find part a. For part b, divide the heat that is supplied to the water by the total heat supplied to the system.

[Anthony Hatashita 4H]

Think of it as two problems, heating up the copper and then heating up the water. You add the two together to get the total.