Chemical Equilibrium

Question 1

What are the features of dynamic equilibrium?

Answer 1

• forward and backward reactions are both happening at the same rate
• so the concentrations of each substance are staying constant
  CAN ONLY HAPPEN FOR A CLOSED SYSTEM

Question 2

When is equilibrium reached in a diagram?

Answer 2

When the lines plateau off

Question 3

What is Le Chatelier’s principle?

Answer 3

If a reaction is at equilibrium and then a change is made in any of the conditions then the position of equilibrium will shift in the direction that opposes the change.

Question 4

What does changing the pressure do to the position of equilibrium?

Answer 4

Increasing the pressure shifts the position of equilibrium in the direction with fewest gas molecules.
Decreasing the pressure shifts the position of equilibrium in the direction with the most gas molecules.

Question 5

What does changing the temperature do to the position of equilibrium?

Answer 5

Increasing the temperature shifts the equilibrium in the endothermic direction.
Decreasing the temperature would shift the equilibrium in the exothermic direction.

Question 6

What would changing the concentration do to the position of equilibrium?

Answer 6

The position of equilibrium would shift in the direction which would minimise the change by using up the additional excess.

Question 7

What would use of a catalyst do to the position of equilibrium?

Answer 7

A catalyst has no effect on the position of equilibrium, since it speeds up the forwards and backwards rates equally.