# Physical chemistry

1. Oct 23, 2004

### tam

I'm actually taking a physical chem course and i have to hand in a report onpartial molar volumes in NaCl solutions...I'm not really sure how the concept works and i'm wondering if anyone could clarify! Thanks

2. Oct 23, 2004

### so-crates

Heh, just did this lab, so lets see if I can help.

The idea with partial molar volumes is that when you mix a certain volume of some substance with a certain volume of another, the total volume in many cases is not simply V(A) + V(B). The total volume can be represented by the equation $$V~=~n_1\overline{V_1}~+~n_2\overline{ V_2}$$, where V is the total volume, n1 and n2 are the quantities of the mixture in moles, and V1 and V2 are defined as the partial molar volumes of the components of the mixture.

We mixed alcohols and water, and its a little different for salts, though I suppose the principle is basically the same.

Last edited: Oct 23, 2004