Le-Chateliers Principle

Le Chaltelier's Principle states that if a chemical system at equilibrium is stressed,

• the system will adjust to increase the stress
• the system will adjust to reduce the stress
• the system will not adjust

If I add a chemical to a system at equilibrium, increasing its concentration,

• the reaction will shift to the same side of the equation where it appears to make more of it

• the reaction will shift to the opposite side of the equation where it appears to use some of it up

• the reaction will not shift

• byproducts (other unwanted chemicals) will be formed to use the excess

2SO_2(g)+O_2(g) ⇌ 2SO_3(g) + Heat

Adding SO_2(g) will

• shift equilibrium right

• shift equilibrium left

• increase rate of reaction

• have no change

2SO₂(g)+O₂(g) ⇌ 2SO₃(g) + Heat

Increasing the temperature will...

• shift equilibrium right

• shift equilibrium left

• increase pressure

• have no change

Hydrogen fluoride is produced by reacting hydrogen with fluorine.

H₂(g) + F₂(g) ⇌ 2HF(g) △H= -542.2 kJ

A stress that would shift the equilibrium towards the products would be to:

• Add HF(g)

• Remove H₂(g)

• Decrease the volume of the reaction vessel

• Decrease the temperature of the reaction vessel