CHEMystery: Acids and Bases: Acid-Base Reactions

Acid-Base Reactions

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An acid-base reaction which involves a protonic acid, may be described as a reaction in which a hydrogen ion is transferred from an acid to a base. The following reactions may be classified as acid-base reactions:

Equation (1) H₂SO₄(l) + Ca(OH)₂(s) ------> CaSO₄(s) + 2H₂O(l)
Equation (2) HCl(aq) + NaOH(aq) ------> NaCl(aq) + H₂O(l)
Equation (3) H₂SO₄(l) + 2NH₃(g) ------> (NH₄⁺)₂SO₄^2-(s)
Equation (4) HBr(g) + C₅H₅N(l) ------> (C₅H₅NH⁺)Br^-(s)
Equation (5) HCl(g) + H₂O(l) ------> H₃O⁺(aq) + Cl^-(aq)

In all of the reactions above, the first reactant is the acid and the second is the base. Note that acid-base reactions such as those illustrated by Equations (1), (3) and (4) don't need to occur in water.

Acid-Base Reactions

Equation (1) H2SO4(l) + Ca(OH)2(s) ------> CaSO4(s) + 2H2O(l) Equation (2) HCl(aq) + NaOH(aq) ------> NaCl(aq) + H2O(l) Equation (3) H2SO4(l) + 2NH3(g) ------> (NH4+)2SO42-(s) Equation (4) HBr(g) + C5H5N(l) ------> (C5H5NH+)Br-(s) Equation (5) HCl(g) + H2O(l) ------> H3O+(aq) + Cl-(aq)