PC-06 — 5-Bullet Exam Cheat Sheet — Summary

Equilibrium constants: Kc = [P]^p/[R]^r; Kp = Kc(RT)^ $\Delta n$ ; $\Delta G$ ° = −RT ln K; ONLY temperature changes K.
Q rule: Q < K → forward; Q > K → backward; Q = K → equilibrium.
Le Chatelier traps: Catalyst → no shift; inert gas at const. V → no effect; temperature → changes K.
pH essentials: [ $H^{+}$ ]weak acid = √(Ka·C); buffer pH = pKa + log([salt]/[acid]); pH + pOH = 14 at 25°C; Ka × Kb = 10^{-14}.
Ksp rules: Precipitation when Qsp > Ksp; common ion reduces solubility; AgCl: s = √Ksp; $Ag_{2}CrO_{4}$ : s = (Ksp/4)^(1/3); pH of 10^{-8} M HCl ≈ 6.98, not 8.