Exam 4

Question 1

T or F: All ionic compounds dissolve in water to some degree?

Answer 1

True

Question 2

Molar solubility

Answer 2

is the molarity of how much your solid breaks down

Question 3

Thermodynamics

Answer 3

energetics of a process, determines if a process is spontaneous

Question 4

Spontaneous

Answer 4

A process will occur without outside intervention
EX: Dropping a pen and it falls to hit the table

Question 5

What does it mean for a reaction if the forward reaction is spontaneous?

Answer 5

If the forward reaction is spontaneous, the reverse reaction is non-spontaneous

Question 6

If I lose energy the rxn is…

Answer 6

spontaneous

Question 7

If I gain energy, the rxn is…

Answer 7

non-spontaneous

Question 8

Water freezing a 5C

Answer 8

non-spontaneous

Question 9

A ball falling to the ground

Answer 9

spontaneous

Question 10

Gasoline lighting on fire at room temperature

Answer 10

non-spontaneous

Question 11

The sunning running out of fuel and dying

Answer 11

spontaneous

Question 12

Gasoline burning at room temperature

Answer 12

spontaneous

Question 13

Entropy

Answer 13

Chaos/disorder

Question 14

2nd Law of Thermodynamics

Answer 14

Any spontaneous rxn MUST increase the entropy of the universe

Question 15

State function

Answer 15

Path independent. Only need to worry about the start and the end

Question 16

Exothermic

Answer 16

heat added to surroundings (taken from system)

Question 17

Endothermic

Answer 17

heat taken from surroundings (added to system)

Question 18

What does thermodynamics help predict?

Answer 18

Whether a process will occur under certain conditions

Question 19

A spontaneous process is one that:

Answer 19

Occurs without ongoing outside intervention

Question 20

Which of the following statements is true about nonspontaneous processes?

Answer 20

They require energy input to occur

Question 21

Spontaneity of a reaction is determined by comparing:

Answer 21

Chemical potential energy before and free energy after the reaction

Question 22

A spontaneous process that goes from a system of lower potential energy to higher potential energy is called:

Answer 22

Endothermic

Question 23

What typically increases as water changes from a solid to a liquid to a gas?

Answer 23

Entropy

Question 24

Which of the following best describes the concept of entropy in this context?

Answer 24

A measure of disorder or randomness

Question 25

According to the second law of thermodynamics, what must happen for a process to be spontaneous?

Answer 25

the entropy of the universe must increase

Question 26

The symbol ΔS refers to a change in:

Answer 26

Entropy

Question 27

What is the formula for calculating a change in entropy (ΔS)?

Answer 27

ΔS = S_final - S_initial

Question 28

what does Gibbs free energy (G) represent in a chemical system?

Answer 28

The maximum amount of work a system can do

Question 29

Which of the following equations is used to calculate ΔG?

Answer 29

ΔG = ΔH - TΔS

Question 30

What must be true for a process to be spontaneous based on ΔG?

Answer 30

ΔG is negative

Question 31

If ΔG = 0 for a reaction, what does this mean?

Answer 31

The reaction is at equilibrium

Question 32

What is the relantionship between ΔG° and the equilibrium constant K?

Answer 32

ΔG° = -RTln(K)

Question 33

If K<1, what can be said about ΔG° and the reaction under standard conditions?

Answer 33

ΔG° is positive; the reverse reaction is spontaneous

Question 34

What is true about ΔG° when K=1?

Answer 34

ΔG° is zero

Question 35

In a voltaic cell, what occurs at the anode?

Answer 35

Oxidation

Question 36

Which electrode is more positively charged in a volatic cell?

Answer 36

Cathode

Question 37

What is the function of the salt bridge in a voltaic cell?

Answer 37

Maintains electrical neutrality by allowing ion flow