Chapter 19 Key Concepts

Question 1

What happens to Kp if you increase temperature and the forward reaction is exothermic

Answer 1

K decreases
System no longer in equilibrium
Equilibrium yield of product decreases and ratio of P/R is now greater than Kp

Pp of the P must decrease and the R must increase. Position of equilibrium shifts left towards the reactants.

New equilibrium recached where P/R is equal to the new Kp

Question 2

What happens to Kp if you increase temperature and the forward reaction is endothermic

Answer 2

K increase
System no longer in equilibrium
Equilibrium yield of product increases and ratio of P/R is now smaller than Kp

Pp of the P must increase and the R must decrease. Postition of equilibrium shifts right towards the products. New equilibrium recached where P/R is equal to the new Kp

Question 3

How does concentration affect Kc

Answer 3

It doesn’t
The ratio changes but then the concentrations must change to return the ratio back to K. This is why the equilibrium position changes

Question 4

How does a Catalyst affect equilibrium

Answer 4

Catalysts affect the rate of the chemical reaction. The speed of the forward and reverse reactions are speed up by the same factor. So equilibrium reached quicker.

position of equilibrium is unaffected