Question

Answer the following question:Be sure to show all your work. Include formulae and units! EVERY TIME! don't forgot to give relavant diagram.

4. A 500-gm aluminum can holds 600 gm of water.How much energy must be used to completely boil away the water if the initial temperature of the can/water system is 30⁰C?Assume that as the water changes temperature, the can changes temperature so that it is always at the same temperature as the water.

Answer 1

specific heat of water is 4.186 kJ/kgC
heat of vaporization of water is 2256 kJ/kg

to heat it to 100C
E = 4.186 kJ/kgC x 0.6 x 70 = 175.812 kJ

to boil it
E = 2256 kJ/kg x 0.6 kg = 1353.6 kJ

hence total Energy/ heat required = 175.812 kJ + 1353.6 kJ =1529.412 kJ Ans.