Enthalpy and Phase Changes Answers

NaCl has a Hfus = 30.2 kJ/mol. What is the mass of a sample of NaCl that needs 732.6 kJ of heat to melt completely?Use .

The molar heat of fusion for water is 6.01 kJ/mol. How much energy must be added to a 75.0-g block of ice at 0°C to change it to 75.0 g of liquid water at 0°C?Use .

What scientific tool would be the most helpful when measuring the temperature of a substance that is undergoing a phase change?

Which term is used to describe the amount of heat that is required to convert 1 mol of a liquid to a gas?

Which scientific tool is the most useful when trying to convert a known amount of grams of water to moles of water?

A chemist wants to calculate the amount of heat that is absorbed by a sample of copper as it is melted. Which constant should she use?

Copper has a Hfus = 13.0 kJ/mol. What mass of copper releases 112.4 kJ of heat as it freezes?Use .

Which energy changes are associated with a liquid boiling?

During an endothermic phase change, what happens to the potential energy and the kinetic energy?

The graph below illustrates a change in energy during a phase change.Which explanation correctly describes the phase change in the graph?