## 29 terms

### When a reaction is said to be exothermic delta H is ________ and delta S (of the surroundings) is ________.

Negative, Positive.

### When a reaction goes from two moles of a gas to one mole of a solid the delta S (of the system) is expected to be ________.

Negative

### When a reaction is exothermic and the entropy is increasing, it is a __________ reaction at ____ temp(s). This is a type __ reaction.

Spontaneous, All, 1

### When a reaction is exothermic and the entropy is decreasing, it is a __________ reaction at ____ temp(s). This is a type __ reaction.

Spontaneous, Low, 2

### When a reaction is endothermic and the entropy is increasing, it is a __________ reaction at ____ temp(s). This is a type __ reaction.

Spontaneous, High, 3

### When a reaction is endothermic and the entropy is decreasing, it is a __________ reaction at ____ temp(s). This is a type __ reaction.

Non-Spontaneous, All, 4

### Gibbs Free Energy Equation is _______. (expressed in terms of entropy only).

-T∆S(universe) = ∆H(system) - T∆S(system)

### Spontaneous changes ________. (finish definition)

Occur only in the direction that leads to equilibrium, naturally and unaided.

### The 2nd law of thermodynamics states that ______.

A spontaneous process is one that results in an increase of the entropy of the universe.

### Statistical Thermodynamics defines entropy as the available ________ for a given reaction.

Microstates

### S =

k ln W

.....where k is the proportionality (Boltzmann's) constant and W is the number of accessible microstates.

### The 3rd law of thermodynamics states that ______.

A perfect crystal at 0 K has zero entropy. (S = 0)

### At equilibrium ∆G = __. Why?

0, because a reaction proceeds spontaneously toward the minimum in free energy, which corresponds to equilibrium.

### A process that is entropy-favored and enthalpy-disfavored occurs when _____ and _____.

∆S° > 0, ∆H° > 0

### A process that is entropy-disfavored and enthalpy-favored occurs when _____ and _____.

∆S° < 0, ∆H° < 0