Chemistry

Name: __________________________ Thermochemistry Worksheet #3

1.

Find the heat associated with the solidification of 30.0 g of water. (Ans: -10.0 kJ)

2.

A reference gives a value of 39.23 kJ/mol for the molar enthalpy of vaporization of methanol. What heat change occurs in the evaporation of 10.0 g of methanol? (Ans: 12.2 kJ)

3.

An experiment produces evidence that the evaporation of 4.00g of liquid butane, C4H10, requires a heat gain of 1.67 kJ. Find the molar enthalpy of vaporization for butane from this evidence. (Ans: 24.3 kJ/mol)

4.

The ∆Hvap for ammonia is 1.37 kJ/mol. Find the mass of ammonia that can be condensed from vapor to liquid during a heat change of 10.0 kJ. (Ans: 124 g)