Thermochemical equilibrium

Question 1

What is a spontaneous process?

Answer 1

When the conditions are right for a process to occur

Question 2

What is a non-spontaneous process?

Answer 2

Energy is required to meet the conditions for the process to occur

Question 3

What is the energy tax?

Answer 3

When energy transitions result in a loss in energy

Question 4

What is entropy (S)?

Answer 4

A measure of the distribution/disorder of energy in a system

Question 5

How do you calculate ΔS(univ)

Answer 5

ΔS(univ) = ΔS(sys) + ΔS(surr)

Question 6

What is a microstate?

Answer 6

A unique distribution of energy among energy levels

Question 7

How do you calculate S?

Answer 7

S = kln(# of microstates)

Question 8

Is a reaction moving from high to low entropy spontaneous or non spontaneous?

Answer 8

Non spontaneous

Question 9

Is a reaction moving from low to high entropy spontaneous or non spontaneous

Answer 9

Spontaneous

Question 10

What is an isothermal process?

Answer 10

A process that occurs at a constant temperature

Question 11

What is a reversible process?

Answer 11

A process that can be run in the opposite direction without net flow in the opposite direction

Question 12

How do you calculate ΔS for a phase change

Answer 12

ΔS = q/T

Question 13

If S>0, is the process spontaneous or non spontaneous?

Answer 13

Spontaneous

Question 14

How does temperature affect entropy?

Answer 14

Entropy increases with increasing temperature

Question 15

How does volume affect entropy?

Answer 15

Entropy increases with increasing volume

Question 16

How does number of particles affect entropy?

Answer 16

Entropy increases with increasing number of particles

Question 17

How does the S(solid) compare to S(liquid) and S(gas)

Answer 17

S(solid) < S(liquid) < S(gas)

Question 18

How does the complexity of the structure affect entropy?

Answer 18

The more complex the structure, the higher entropy will be

Question 19

How does the rigidity of the structure affect entropy?

Answer 19

The more rigid the structure, the lower entropy will be

Question 20

How is entropy change of a system calculated?

Answer 20

ΔSrxn = ∑nΔS (products) - ∑nΔS (reactants)

Question 21

What is free energy (G)?

Answer 21

Energy available to do work

Question 22

If ΔG < 0, is the process spontaneous or not?

Answer 22

It is spontaneous

Question 23

What is the relationship between S, H, and T?

Answer 23

ΔS = -ΔH/T

Question 24

What is the relationship between G, S, H, and T?

Answer 24

G = H - TS

Question 25

What does it mean when ΔG is a large negtaive number?

Answer 25

Reaction is spontaneous, and products are favored

Question 26

What does it mean when ΔG is a large positive number?

Answer 26

Reaction is non spontaneous, and reactants are favored

Question 27

What does it mean when ΔG is a small negative or small positive number?

Answer 27

There is an equal amount of reactant and products