6 - Equilibrium constant Kc for homogeneous systems

Question 1

What is meant by K_c?

Answer 1

Equilibrium constant

Question 2

What is the K_c equation?

Answer 2

K_c = [Products]^x / [Reactants]^x

x superscript = Number of moles of substance

Question 3

What does a low K_c value indicate?

Answer 3

• More reactants
• Equilibrium lies to the left

Question 4

What does a high K_c value indicate?

Answer 4

• More products
• Equilibrium lies to the right

Question 5

What factor affects K_c?

Answer 5

Temperature

(Concentration, pressure or a catalyst does not affect K_c)

Question 6

If the temperature is increased, what will happen to the value of K_c if the fowards reaction is exothermic?

Answer 6

The position of equilibrium shifts to the left (reactants) so the value of K_c gets smaller as there are fewer products

Question 7

How can we calculate the moles of reactant at equilibrium?

Answer 7

Moles of reactant at equilibrium = initial moles - moles reacted

Question 8

How can we calculate the moles of products at equilibrium?

Answer 8

Moles of product at equilibrium = initial moles + moles formed