Editing Molar concentration (section)

== Related quantities ==
=== Number concentration ===
The conversion to [[number concentration]] <math>C_i</math> is given by

:<math>C_i = c_i N_\text{A},</math>

where <math>N_\text{A}</math> is the [[Avogadro constant]].

=== Mass concentration ===
The conversion to [[mass concentration (chemistry)|mass concentration]] <math>\rho_i</math> is given by

:<math>\rho_i = c_i M_i,</math>

where <math>M_i</math> is the [[molar mass]] of constituent <math>i</math>.

=== Mole fraction ===
The conversion to [[mole fraction]] <math>x_i</math> is given by

:<math>x_i = c_i \frac{\overline{M}}{\rho},</math>

where <math>\overline{M}</math> is the average molar mass of the solution, <math>\rho</math> is the [[density]] of the solution.

A simpler relation can be obtained by considering the total molar concentration, namely, the sum of molar concentrations of all the components of the mixture:

:<math>x_i = \frac{c_i}{c} = \frac{c_i}{\sum_j c_j}.</math>

=== Mass fraction ===
The conversion to [[mass fraction (chemistry)|mass fraction]] <math>w_i</math> is given by

:<math>w_i = c_i \frac{M_i}{\rho}.</math>

=== Molality ===
For binary mixtures, the conversion to [[molality]] <math>b_2</math> is

:<math>b_2 = \frac{c_2}{\rho - c_1 M_1},</math>

where the solvent is substance 1, and the solute is substance 2.

For solutions with more than one solute, the conversion is

:<math>b_i = \frac{c_i}{\rho - \sum_{j\neq i} c_j M_j}.</math>