Thermo II Exam 2

Question 1

Amagat’s Law

Answer 1

Delta V on mixing for non-reacting gases is zero.

Question 2

substitute for Amagat’s law

Answer 2

Applicable only at low pressure

z is a linear factor of the mole fraction

Question 3

Amagat’s Law assumption is used for…

Answer 3

Lewis-Randall Rule

Question 4

Activity Coefficient equations

Answer 4

Alpha_i(T,P,X) = (overbar) F_iL (T,P,X) /x_i*f_iL(T,P)

Question 5

Liquid Phase Approaches

Answer 5

Activity Coefficient Models

Cubic - EOS

Question 6

Simple Liquid Mixture

Answer 6

Formed by mixing two or more pure species that are liquids at the T,P of the mixture

Question 7

Nonsimple Liquid Mixture

Answer 7

Formed by mixing two or more pure species of which at least one of the components is not a liquid at the T, P, of the mixture

Question 8

Requirements for Excess Gibbs Energy (Activity Coefficient) Models, assuming binary Mixture

Answer 8

1. Must satisfy Gibbs Duham Equation
2. as x1 –> 0, G^ex –> 0
3. as x1 –> 0, G^ex –> 0

Question 9

Random Mixture

Answer 9

Mixing 2 or more components in which the molecules are arranged randomly (Ideal gases, Ideal liquid mixtures, butane and isobutane)

Question 10

One-Constant Margules Notes

Answer 10

1. A may be positive or negative
2. A is generally a function of temperature
3. A may be assumed constant over small temperature range
4. Satisfactory results for mixtures composed of molecules of similar size, shape, and chemical natures

Question 11

Van Laar Equations Assumptions

Answer 11

1. Applicable to binary mixtures
2. Species are of similar size and interaction energies

Question 12

Local Composition Models

Answer 12

Something causes preferential arrangement in a mixture on a microscopic level (polarity, hydrophobic/hydrophilic, large size differences)