Number density via volumetric density and molar mass

Number density, or number of molecules per unit volume, can be expressed using the volumetric density, or mass per unit volume, and molar mass, or mass per unit amount of substance.

Notation:

  1. \(N_\text{A}\) (N_A) is avogadro_constant.

Links:

  1. Wikipedia.

number_density

Number density, or number of molecules per unit volume.

Symbol:

n

volumetric_density

Volumetric density, or mass per unit volume.

Symbol:

rho

Latex:

\(\rho\)

molar_mass

Molar mass, or mass per unit amount of substance.

Symbol:

M

law

n = rho * N_A / M

Latex:
\[n = \frac{\rho N_\text{A}}{M}\]