Entropy/free energy

Question 1

Define entropy

Answer 1

The dispersal of energy in a system

Question 2

What is the symbol for entropy?

Answer 2

S

Question 3

What is the unit of entropy?

Answer 3

Joules per Kelvin per mole (JK-1mol-1)

Question 4

How could you predict the entropy change of a reaction?

Answer 4

• look out for change in mol of gas

- look out for a change in state

Question 5

From highest to lowest entropy, order the states of matter

Answer 5

gas
solution
liquid
solid

Question 6

How would entropy be affected if there was an increase in mol of gas?

Answer 6

increase in entropy

Question 7

How would entropy be affected if there was a decrease in mol of gas?

Answer 7

decrease in entropy

Question 8

Is an increase in entropy favoured?

Answer 8

Yes

Question 9

Define sponteanous process

Answer 9

A process that is energetically possible

Question 10

Define feasible process

Answer 10

A process that is energetically possible

Question 11

Is standard entropy change always positive?

Answer 11

Yes

Question 12

Define standard entropy

Answer 12

The entropy of one mole of a substance under standard conditions

Question 13

What are standard conditions?

Answer 13

298K

100KPa

Question 14

What is sign of ΔG for feasible processes?

Answer 14

-

Question 15

What is the formula for Gibbs’ free energy?

Answer 15

ΔG= ΔH- TΔS

Question 16

What are the units for Gibbs’ free energy (ΔG)?

Answer 16

kJmol-1

Question 17

What are the units for ΔH?

Answer 17

kJmol-1

Question 18

What must T be in to calculate ΔG?

Answer 18

K(elvin)

Question 19

What must ΔS be converted from and to?

Answer 19

From J per K per mol to kJ per K per mol