In the preceding problem, suppose that the copper block is dropped into the water from a height of 50 m. Assuming no loss of water from the tank, what is the change in internal energy of the block?
In the following take CV = 5 and CP = 7 cal/mol-K for nitrogen gas:
(a) Five moles of nitrogen at 100 °C is contained in a rigid vessel. How much heat must be added to the system to raise its temperature to 300 °C if the vessel has a negligible heat capacity? (ANS. 5000 cal) If the vessel weighs 80 g and has a heat capacity of 0.125 cal/g-K, how much heat is required?
(b) Five moles of nitrogen at 300 °C is contained in a piston/cylinder arrangement. How much heat must be extracted from this system, which is kept at constant pressure, to cool it to 100 °C if the heat capacity of the piston and cylinder is neglected?
