7.10 Reaction Quotient & Le Châtelier

Q < K → too few products → shift right. Q > K → too many products → shift left. Q = K → at equilibrium.

This is the quantitative justification AP wants for Le Châtelier shifts.

Justify a shift: 'Adding X increases Q above K, so the reaction proceeds in reverse.'

Worked example: K = 10, Q = 2 → net forward reaction.