The partial specific volume

\bar,

express the variation of the extensive volume of a mixture in respect to composition of the masses. It is the

partial derivative In mathematics, a partial derivative of a function of several variables is its derivative with respect to one of those variables, with the others held constant (as opposed to the total derivative, in which all variables are allowed to vary). Pa ...

of volume with respect to the mass of the component of interest. :

V=\sum _^n m_i \bar,

where

\bar

is the partial specific volume of a component

i

defined as: :

\bar=\left( \frac \right)_.

The PSV is usually measured in milliLiters (mL) per

gram The gram (originally gramme; SI unit symbol g) is a unit of mass in the International System of Units (SI) equal to one one thousandth of a kilogram. Originally defined as of 1795 as "the absolute weight of a volume of pure water equal to ...

(g), proteins > 30 kDa can be assumed to have a partial specific volume of 0.708 mL/g. Experimental determination is possible by measuring the natural frequency of a U-shaped tube filled successively with air, buffer and protein solution.

Properties

The sum of partial specific volumes of a mixture or solution is an inverse of density of the mixture namely the specific volume of the mixture. :

v = \sum_i w_i\cdot \bar = \frac

\sum_i \rho_i \cdot \bar = 1

Properties

Notes

See also