1 To treat a burn on your hand you decide to place an ice cu

1. To treat a burn on your hand, you decide to place an ice cube on the burned skin. The mass of the ice cube is 12.9 g, and its initial temperature is -13.9

Solution

1. Initial state - Ice at -13.9 oC

Final state - water at 30.2 oC

Heat for ice to go from -13.9 to 0 = 2.12*12.9*13.9 = 380.14 J

Heat for ice to go to water at 0 oC = 336*12.9 = 4334.4 J

Heat for water to go from 0 to 30.2 oC = 30.2*12.9*4.2 = 1636.24 J

So total heat required = 1636.25 + 4334.4 + 380.14 = 6350.78 J

2. VP at 23 oC = 92.0 Torr

VP at 45 oC = 265.0 Torr

Delta H vap = R*(lnP2/P1)/(1/T1 - 1/T2) = 109637.72 J