{{More citations needed|date=January 2021}} The '''partial specific volume''' '''<math>\bar{v_i},</math>''' express the variation of the extensive volume of a mixture in respect to composition of the masses. It is the partial derivative of volume with respect to the mass of the component of interest. :<math>V=\sum _{i=1}^n m_i \bar{v_i},</math>
where <math>\bar{v_i}</math> is the partial specific volume of a component <math>i</math> defined as:
:<math>\bar{v_i}=\left( \frac{\partial V}{\partial m_i} \right)_{T,P,m_{j\neq i}}.</math>
The PSV is usually measured in milliLiters (mL) per gram (g), proteins > 30 kDa can often be assumed to have a partial specific volume of 0.708 mL/g, though this estimate varies depending on the amount of volume accessible by solvent or bound molecules.<ref>{{cite book |last1=Buxbaum |first1=Engelbert |title=Biophysical Chemistry of Proteins |url=https://archive.org/details/biophysicalchemi00buxb_979 |url-access=limited |date=2011 |publisher=Springer |location=New York, Dordrecht, Heidelberg, London |isbn=978-1-4419-7250-7 |pages=[https://archive.org/details/biophysicalchemi00buxb_979/page/n236 237]–249 |chapter=25: Centrifugation|doi=10.1007/978-1-4419-7251-4_25 }}</ref> Experimental determination is possible by measuring the natural frequency of a U-shaped tube filled successively with air, buffer and protein solution.<ref>{{cite book |author1=Kratky, O. |author2=Leopold, H. |author3=Stabinger, H. |editor1=Hirs, C.H.W. |editor2=Timasheff, S.N. |title=Meth. Enzymol. Vol. 27: Enzyme Structure Part D|date=1973 |isbn=978-0-12-181890-6 |pages= 98–110 |chapter=5: The determination of the partial specific volume of proteins by the mechanical oscillator technique}}</ref>
==Properties== The weighted 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. :<math>v = \sum_i w_i\cdot \bar{v_i} = \frac {1}{\rho}</math>
:<math>\sum_i \rho_i \cdot \bar{v_i} = 1</math>
==See also== *Partial molar property *Apparent molar property
==References== <references/>
Category:Mass density
{{Chem-stub}} {{Biochem-stub}}