Thermodynamics of Mixing

This text discusses the thermodynamics of mixing, including the definition of partial molar quantities, deviations from ideal mixing, and the calculation of partial molar volumes.

Questions

• What are partial molar quantities?
• What are deviations from ideal mixing?
• How can partial molar volumes be calculated?

Answers

• Partial molar quantities are the thermodynamic properties of a component in a mixture, divided by the number of moles of that component in the mixture.
• Deviations from ideal mixing occur when the interactions between the molecules in the mixture are not the same as the interactions between the molecules in the pure components.
• Partial molar volumes can be calculated experimentally by fixing the number of moles of one component in a mixture and varying the number of moles of the other component. The partial molar volume of the first component can then be calculated from the slope of the plot of the total volume of the mixture versus the number of moles of the second component.