Chem 12 - Equilibrium

Equilibrium

A state that exists in a reversible chemical change in which the rate formed is equivalent to the rate reverse

First condition for EQM

Rate forward = Rate reverse

2nd condition for EQM

Reversible reaction must be possible

Third condition for EQM

Closed system (no matter in or out)

Fourth condition of EQM

Isothermic (no energy in or out)

Fifth condition of EQM

Can be achieved from either direction or the middle

Sixth condition of EQM

Once achieved, no macroscopic changes

Le Chatelier’s Principle

When a system at equilibrium is stressed, the system will shift in such a way as to reduce the imposed stress until a new equilibrium is established

Stress

Differentials affects the rate

Keqm > 1

Products are favoured

Keqm < 1

Reactants are favoured

Keqm ≈ 1

Neither reactants or products are favoured

Stress that always caused a shift

Change temperature