Normality Calculator
Normality (N) is the number of gram-equivalents of solute per litre. Used in acid-base and redox titrations.
How to use this normality calculator
- Enter the mass of solute in grams.
- Calculate equivalent weight = molar mass ÷ n-factor (number of H⁺, OH⁻, or electrons per formula unit).
- Enter volume in mL.
- Example: 49g H₂SO₄ (eq wt=49 g/eq) in 1000 mL → 1.000 N.
Formula
Normality (N) = gram equivalents ÷ volume (L). Gram equivalents = mass ÷ equivalent weight. Equivalent weight = molar mass ÷ n-factor.
About the Normality Calculator
Normality simplifies titration calculations: at the equivalence point, N₁V₁ = N₂V₂ always holds — 25 mL of 1 N H₂SO₄ requires exactly 25 mL of 1 N NaOH, even though the mole ratio is 1:2.
This convenience made normality the standard in classical analytical chemistry. Modern labs increasingly use molarity with explicit stoichiometry, but normality remains valuable wherever the equivalence relationship simplifies calculations.
Frequently asked questions
+What is normality?
Normality (N) = gram-equivalents of solute per litre. It accounts for the reactive 'power' of each formula unit — how many protons, hydroxides, or electrons it provides.
+What is equivalent weight?
Equivalent weight = molar mass ÷ n-factor. N-factor = H⁺ donated (acid), OH⁻ donated (base), or electrons transferred (redox). H₂SO₄: MM=98, n=2, eq wt=49.
+Is normality still used?
Less than before — IUPAC prefers molarity. But normality persists in titrations, water chemistry, and some clinical labs because N₁V₁ = N₂V₂ holds for any acid-base or redox pair without tracking stoichiometry.