Chemical Equilibrium

Question 1

Define dynamic and equilibrium

Answer 1

Dynamic: both forward and backward reactions are still occurring at the same time

Equilibrium: proportion of reactants and products are unchanging

Question 2

What will a change in conditions cause

Answer 2

It will cause the equilibrium to shift to counteract that change

Question 3

How does concentration affect the equilibrium

Answer 3

1. Increase concentration of reactants will shift to RHS as it favours the forward reaction and also increases the yield

Question 4

How does pressure affect the equilibrium

Answer 4

Increase in pressure causes equilibrium to shift to the side with fewer miles

Question 5

How does temperature affect the equilibrium

Answer 5

Increase in temperature will favour endothermic

Decrease in temperature will favour exothermic

Question 6

What are the conditions used in the haber process and why are they used

Answer 6

1. 450 C- not higher as it decrease the yield and not lower as the reaction would be too slow
2. 250 atm- not higher as its too expensive not lower as the equilibrium will shift to the side with fewer moles
3. Iron catalyst- cheaper as it speeds up a reaction without being used up
4. Removal of ammonia- equilibrium shifts to RHS to increase the yield

Question 7

Describe the haber process

Answer 7

1. Nitrogen from air and hydrogen from methane
2. These are compressed at 250 atm
3. They are then transferred into a reaction chamber with a iron catalyst and ammonia gas is formed in this reaction
4. This then goes to a heat exchanger where the heat is recycled to the reaction chamber
5. This then goes to a condenser where nitrogen, hydrogen and ammonia gas are recycled back to the reaction chamber
6. The liquid ammonia then goes to a storage vessel

Question 8

What is a reversible reaction

Answer 8

It’s where the products react to produce the original reactants ie. an equilibrium is reached