Thermodynamics

Question 1

Spontaneous Process (Spontaneity)

Answer 1

reaction that occurs by itself, without any outside intervention (energy input)

Question 2

Entropy

Answer 2

number of energetically equivalent ways to arrange the components (particles) of a system

Question 3

More ways to arrange particles does what to entropy?

Answer 3

the more ways to arrange particles, the more randomized the particles are in a chemical system, so the higher the entropy

Question 4

Changes that increase the entropy of a system

Answer 4

Change in State
Solids dissociating in H2O
Increase in temperature
Rxns with more products than reactants

All of these changes have a positive DeltaS
All of these processes above result in a greater randomization of particles -> increase in entropy

Question 5

Any spontaneous process must increase the entropy in the universe, according to what?

Answer 5

Second Law of Thermodynamics

Question 6

Gibbs Free Energy

Answer 6

the chemical potential of chemical systems tries to get to the lowest chemical potential (equilibrium)

Question 7

For a spontaneous reaction pure products and reactants move where in the graph?

Answer 7

Move downhill toward the lowest chemical potential (@ equilibrium)

Question 8

For a spontaneous and non-spontaneous reaction, what are the signs of DeltaG?

Answer 8

(-) DeltaG = spontaneous rxn
(+) DeltaG = nonspontaneous rxn

Question 9

What is the equation for Gibbs Free Energy?

Answer 9

DeltaG = DeltaH - TDeltaS

Question 10

What Delta H and Delta S values are spontaneous at all temperatures?

Answer 10

DeltaH = (-)
DeltaS = (+)

Question 11

Increasing molecular complexity (more molecules) and increasing molar mass does what to the entropy of a system?

Answer 11

Produces a greater amount of energy because there is more places to put that energy

Question 11

What are the standard conditions of a solution (Free Energy Changes)?

Answer 11

Concentration: 1M
Pressure: 1 atm
Temp: 25C or 298K

Question 11

What is the equation for DeltaGrxn and when would we apply that equation?

Answer 11

Equation: DeltaGrxn = DeltaG* + RTlnQ
We would apply this equation when reactants and products are in their standard state conditions.

Question 11

What is the equation for standard Gibbs free energies of formation?

Answer 11

DeltaG = [moles (products)] - [moles (reactants)]

Question 11

When calculating the standard Gibbs free energies of formation, what is the value of an element in its natural state?

Answer 11

0

Question 12

What are all of the values of a DeltaGrxn?

Answer 12

R = 8.134 J/mol x k
T = Temp
Qp = PH2O

Question 13

Pure Products

Answer 13

Q > K

Question 14

Pure Reactants

Answer 14

Q < K

Question 15

Draw the Gibbs Free Energy graph for a chemical reaction!

Question 16

At equilibrium DeltaG =

Answer 16

0

Question 17

Calculate DeltaG (in notebook)

Question 18

Calculate crossover temperature (in notebook)

Question 19

Which state of matter has more ways to arrange a particle and how does this relate to entropy?

Answer 19

For a gas there are more ways to arrange a particle, thus higher entropy.

Question 20

What type of molecules have the most amount of ways you can arrange those atoms?

Answer 20

Complex Molecules

Question 21

Does the size of an atom have any relation to energy dispersed?

Answer 21

The bigger the atom, the more space for energy to be disperesed

Question 22

Why would a aqueous solution have a higher randomization?

Answer 22

Because of the ions present in the solution.

Question 23

Example 1 of GFE (in notebook)

Question 24

Example 2 of GFE (in notebook)

Question 25

Example 1 for Calculating DeltaGf (in notebook)

Question 26

Example 2 Calculate DeltaG from DeltaH and DeltaS (in notebook)

Question 27

Example 3 Calculate DeltaG rxn for the rxn (in notebook)

Question 28

Calculate DeltaG under non-standard conditions (in notebook) and when PH20 is a different value

Question 29

What is the equation for DeltaG and the equilibrium constant?

Answer 29

DeltaG = -RTlnK

Question 30

Spontaneous in the forward direction corresponds to what value of DeltaG and what relationship with K?

Answer 30

DeltaG* = (-)
K > 1

Question 31

Non-spontaneous in the forward direction corresponds to what value of DeltaG and what relationship with K?

Answer 31

DeltaG = (+)
K < 1

Question 32

Caculate DeltaG* for an equilibrium constant (in notebook)