Acids, Bases & Salts — 60 Terms Defined

Relationship between Ka and Kb Acids, Bases & Salts Dimensionless The reciprocal link between the strengths of an acid and its conjugate base. Ka × Kb = Kw

Salt Acids, Bases & Salts Dimensionless An ionic compound formed when the hydrogen of an acid is replaced by a metal or other cation. acid + base → salt + water

Salt Hydrolysis Acids, Bases & Salts mol/L The reaction of a salt's ions with water to produce an acidic or alkaline solution. A⁻ + H₂O ⇌ HA + OH⁻

Self-Ionisation of Water Acids, Bases & Salts mol/L The reaction in which two water molecules transfer a proton to give a hydronium and a hydroxide ion. 2H₂O ⇌ H₃O⁺ + OH⁻

Stepwise Ionisation Acids, Bases & Salts mol/L The successive loss of protons from a polyprotic acid, each governed by its own equilibrium constant. Ka₁ ≫ Ka₂ ≫ Ka₃

Strong Acid Acids, Bases & Salts mol/L An acid that ionises essentially completely in aqueous solution. HA → H⁺ + A⁻ (complete)

Strong Base Acids, Bases & Salts mol/L A base that dissociates or ionises completely in aqueous solution to give hydroxide ions. BOH → B⁺ + OH⁻

Superacid Acids, Bases & Salts Dimensionless An acid stronger than pure sulfuric acid, capable of protonating species normally regarded as completely non-basic. H₀ < −12

Titration Acids, Bases & Salts mol/L A quantitative technique in which a solution of known concentration is added to another until the reaction between them is exactly complete. n₁ / n₂ = a / b

Titration Curve Acids, Bases & Salts Dimensionless A plot of pH against the volume of titrant added during an acid–base titration.

Weak Acid Acids, Bases & Salts mol/L An acid that ionises only partially in aqueous solution, establishing an equilibrium with its conjugate base. HA ⇌ H⁺ + A⁻

Weak Base Acids, Bases & Salts mol/L A base that accepts protons only partially in aqueous solution, establishing an equilibrium. B + H₂O ⇌ BH⁺ + OH⁻