1. Free energy and work we can measure T, P, V and n q = CT mass
qirreversible
qreversible
constant P
constant T
qP = n CPT
= H
qr = nRTln(V2/V1)
ideal gas,
CP = 5/2 R
qr = TS
constant V
qV = n CVT
= E
ideal gas,
CV = 3/2 R
constant T
(ideal gas)
q = PV

2. Free energy and work we can measure T, P, V and n wmax = wuseful max
+ wPV
wPV
wuseful
wmax
max
wPV = -Pext  V
wuseful = G
max
wmax= - nRT ln(V2/V1)
E = q + w
E = qr
+ wuseful
max
+ wPV
reversible conditions
H - PV =
qr + wuseful + wPV
max
H - PextV =
qr + wuseful
max
- PextV
H =
TS
+ wuseful
max
H - TS
= wuseful
max
= G

3. Free energy and work E = q + w = qr + wr q + wuseful + wPV = qr
max
+ wPV q
+ wuseful
= qr
+ wuseful
max
q - qr
= wuseful
max
- wuseful
under constant P and T
if wuseful = 0
if wuseful = wuseful
max
wuseful
max
= q - qr
q = qr
q =
wuseful
max
+ qr
q = TS P
q = G
+ TS
= H P

4. Standard Gibbs Free Energy
Go =
Ho
- TSo
Go < 0
spontaneous
Go = kJ/mol
Go > 0
non-spontaneous
Go = kJ/mol
Go = 0
equilibrium
Go = kJ/mol
glucose
+ phosphate 
glucose-6-phosphate
+ H2O
ATP
+ H2O 
ADP
+ phosphate
glucose
+ ATP
 ADP +
glucose-6-phosphate

5. Non-standard conditions
reaction quotient
= [products] m
Q =
initial
[reactants] n
initial
K =
equilibrium constant
= [products] m
equilibrium
[reactants]
equilibrium n
G =
- RT
ln ( ) K /Q
K > Q
G < 0
spontaneous
G > 0
K < Q
non-spontaneous
K = Q
G = 0
equilibrium

6. Go G = - RT ln(K) o G = - RT ln(K/Q) Standard Free Energy
Impose Standard conditions:
[reactants]initial
= 1(M or atm)
= [products]initial
Q = 1
G =
- RT ln(K) o
Standard Free Energy

7. Non-Standard Conditions
G =
Go
+ RT ln Q
G = - RT ln (K/Q)
Go = - RT ln K
ln (a/b) =
ln a
- ln b
G = - RT ln (K/Q) =
-RT ln K
+ RT ln Q

8. Go = - RT ln(K) G = - RT ln ( ) K /Q G < [products] glucose
+ phosphate 
glucose-6-phosphate
+ H2O
standard conditions
non-spontaneous
Go = kJ/mol
= -RT ln K
K =
1.2 x 10-3
-RT
G =
- RT
ln ( ) K /Q G
< Q
< K
<
1.2 x 10-3
non-standard conditions
[products]
[reactants]
initial
Q =
start with no product
spontaneous

9. Non-Standard Conditions
G =
Go
+ RT ln Q
2NO2 (g) N2O4 (g)
Initially
[NO2] = 0.3 M
[N2O4] = 0.5 M
Will more products or reactants be formed?
Q =
0.5 /
0.32
= 5.6

10. Non-Standard Conditions
G =
Go
+ RT ln Q
2NO2 (g) N2O4 (g)
Initially
[NO2] = 0.3 M
[N2O4] = 0.5 M
Gorxn = Gof products - Gof reactants =
2(51.3) =
- 4.8 kJ/mol
Grxn=
-4.8 +
(8.314 x 10-3)(298)
ln 5.6
= -0.5 kJ/mol
More will be formed
a) product
b) reactant

11. G = -RT ln (K/Q) A +B  C
K =
[C]e
Q =
[C]i
[A]e[B]e
[A]i[B]i
Le Chatelier’s Principle
Add A
a) increase
b) decrease
decrease Q
K/Q
> 1
Add B G
>
< 0
Remove A
increase Q
K/Q
< 1

12. Temperature dependence of K
exothermic reaction
heat =
product
at low T
favor reaction
a) forward
b) reverse
at high T
favor reaction
reverse
endothermic reaction
heat =
reactant
at low T
favor reaction
reverse
at high T
favor reaction
forward

13. Temperature dependence of K
Go = -RT ln K
Go =  Ho - TSo
-RT ln K =
 Ho - TSo
- Ho R 1 T
+ So R
ln K = +
ln K y m x b
exothermic
Ho < 0
1/T
increase T
decrease K T

14. Temperature dependence of K
Go = -RT ln K
Go =  Ho - TSo
-RT ln K =  Ho - TSo
- Ho R 1 T
+ So R
ln K = -
ln K y m x b
endothermic
H > 0
1/T
increase T
increase K T