equilibrium - Kc and Kp Flashcards
1
Q
equation for Kc
A
Kc = [products] / [reactants]
2
Q
what is homogenous equilibria
A
- species all have the same state
3
Q
what is heterogenous equilibria
A
- species with different states
- only include gases/aq in the Kc expression
4
Q
mole fraction equation
A
x(A) = number of moles of A / total moles in gas mixture
sum of MF = 1
5
Q
partial pressure equation
A
p(A) = x(A) x total pressure in system
6
Q
Kp expression
A
Kp = p(products) / p(reactants)
- only include gases
7
Q
magnitude of K relate to eq position
A
K = 1 : eq halfway between R + P K = greater than 1 : towards P K = less than 1 : towards R
8
Q
effect of temp on Kp
A
Exothermic:
- temp inc
- Kp decreases
- eq shifts to left
Endothermic
- temp inc
- Kp inc
- eq shifts to the right
9
Q
effect of conc + pressure on K
A
- no effect
10
Q
catalyst effect on k
A
- no effect
- catalysts affect rate of a reaction
- not the position of equilibrium
- speed up forward and reverse reaction by the same factor
- so equilibrium is reached quicker.