Normality Calculation

The normality of a solution is the gram equivalent weight of a solute per liter of solution. A gram equivalent weight or equivalent is a measure of the reactive capcity of a given chemical species (ion, molecule, etc.). Normality is the only concentration unit that is reaction dependent. Here's an example of how to calculate the normality of a solution.

Normality Example #1

1 M sulfuric acid (H₂SO₄) is 2 N for acid-base reactions because each mole of sulfuric acid provides 2 moles of H⁺ ions.

1 M sulfuric acid is 1 N for sulfate precipitation, since 1 mole of sulfuric acid provides 1 mole of sulfate ions.

Normality Example #2

36.5 grams of hydrochloric acid (HCl) is a 1 N (one normal) solution of HCl.

A normal is one gram equivalent of a solute per liter of solution. Since hydrochloric acid is a strong acid that dissociates completely in water, a 1 N solution of HCl would also be 1 N for H⁺ or Cl^- ions for acid-base reactions.