1 : Kc and Kp Conversion

For a reaction $$[aA + bB \rightleftharpoons cC + dD],$$ where ∆n is the change in moles of gas: $$[Kp = Kc(RT)^{\Delta n}]$$

1 : Chemical Equilibrium

Chemical equilibrium is a state in a chemical reaction where the concentrations of reactants and products remain constant over time. It’s represented as follows: $$[aA + bB \rightleftharpoons cC + dD]$$

2 : Equilibrium Constant for the Reverse Reaction

If Kc is the equilibrium constant for the forward reaction, then (Kc’) for the reverse reaction is: $$[Kc’ = \frac{1}{Kc}]$$

2 : Law of Mass Action

The rate of a chemical reaction is directly proportional to the product of the active masses (concentrations) of the reactants, each raised to the power of its stoichiometric coefficient.

3 : Equilibrium Constant for the Sum of Reactions

If a reaction can be expressed as the sum of two or more reactions, then the equilibrium constant for the overall reaction is the product of the equilibrium constants for the individual reactions.

3 : Equilibrium Constant (Kc)

For the general reaction $$[aA + bB \rightleftharpoons cC + dD],$$ the equilibrium constant Kc is given by: $$[Kc = \frac{[C]^c [D]^d}{[A]^a [B]^b}]$$

4 : Relationship between Kp and Kc for Gas-Phase Reactions

For a reaction involving gases, you can use the ideal gas law to relate Kp and Kc: $$[Kp = Kc(RT)^{\Delta n}]$$ Where R is the ideal gas constant, and T is the temperature in Kelvin.

4 : Le Chatelier’s Principle

When a system at equilibrium is disturbed by a change in concentration, pressure, or temperature, it will shift its position to counteract the disturbance and re-establish equilibrium.

5 : Nernst Equation

For cell equilibrium reactions, the Nernst equation relates the cell potential (E) to the equilibrium constant (K) and concentrations: $$[E = E^\circ - \frac{0.0592}{n} \log \frac{[C]^c [D]^d}{[A]^a [B]^b}]$$ Where E° is the standard cell potential, n is the number of electrons transferred, and [A], [B], [C], and [D] are the concentrations of species involved.

5 : Reaction Quotient (Q)

Similar to Kc, Q is calculated using concentrations, but it’s used to determine the direction in which a reaction will proceed at a given moment.

6 : Ionization Constants (Ka and Kb)

For weak acids (HA) and weak bases (BOH), respectively: $$[Ka = \frac{[H^+][A^-]}{[HA]}]$$ $$[Kb = \frac{[OH^-][BH^+]}{[BOH]}]$$

7 : Solubility Product Constant (Ksp)

For sparingly soluble salts like AgCl: $$[Ksp = [Ag^+][Cl^-]]$$