Question

why volume of water does not increase when some salt put in it.

Answer 1

Because the volume of water is the space occupied by the water and thus it is not affected by addition of common salt (NaCl) into it.

Answer 2

Explanation:

At low salt concentrations the dissociation of the salt causes a contraction of water molecules around the ions;

• thus the reason for the lack of strict additivity.

• As NaCl is added to water the density of the solution increases so the specific volume decreases.