What does normality mean in chemistry

The normality (Unit symbol: N) is an outdated measure of concentration in chemistry, which is mainly used in redox and acid / base reactions. It is not part of the DIN standards. It was determined by the equivalent concentration (unit symbol: ceq) replaced.

Normality is the number of gram equivalents or val dissolved in one liter of a solution. A gram equivalent is the mass of substance that one mole of e.g. protons (H.+Ions) or can give up or take in electrons.

In contrast to molarity, the degree of dissociation and the valency, i.e. how many protons per molecule can be taken up or released, also play a role in the normality of an acid or base.

Like all volume-related content specifications, normality is also temperature-dependent.


Normality is defined by the equation:


Here is N normality, c the molar concentration and z the value.


For example, to make a 1 N solution, 36.5 g HCl, 49 g H2SO4, 40 g NaOH or 85.5 g Ba (OH)2 so much solvent - usually water or alcohol - is added that exactly one liter of solution is produced.

Sodium carbonate (Na2CO3) consists of two sodium ions (Na+) and a carbonate ion. Thus, a 1 molar (M) sodium carbonate solution corresponds to a 2 normal (N) sodium carbonate solution based on the sodium ions (z = 2).

See also


  • Hans R. Christen, Gerd Meyer: Basics of general and inorganic chemistry. Salle + Sauerländer, 1997, ISBN 3793554937
  • Frank H. Stepheson: Math in the laboratory. Elsevier Verlag, Munich 2004, ISBN 3-8274-1596-9

Category: Chemical quantity