In thermodynamics, the specific volume of a substance (symbol: ν, nu) is the quotient of the substance's volume (V) to its mass (m):

It is a mass-specific intrinsic property of the substance. It is the reciprocal of density ρ (rho) and it is also related to the molar volume and molar mass:

The standard unit of specific volume is cubic meters per kilogram (m³/kg), but other units include ft³/lb, ft³/slug, or mL/g.

Specific volume for an ideal gas is related to the molar gas constant (R) and the gas's temperature (T), pressure (P), and molar mass (M) as shown:

Since ${\displaystyle PV={nRT}}$ and ${\textstyle n={\frac {m}{M}}}$

Specific volume is commonly applied to:

Imagine a variable-volume, airtight chamber containing a certain number of atoms of oxygen gas. Consider the following four examples:

Specific volume is a property of materials, defined as the number of cubic meters occupied by one kilogram of a particular substance. The standard unit is the meter cubed per kilogram (m³/kg or m³·kg⁻¹).