1. The synthesis of aluminum from aluminum oxide is energy intensive, and recycling (remelting) is less expensive. Calculate the energy required to heat 1 kg of Al to its melting point and compare that to the energy required to value quoted in the text for Al smelting. The constant pressure heat capacity and the heat of fusion of Al are:

Cp 5 20:67 1 0:01238T J mol21 K21 Hf 5 10; 700 J mol21