The volume of a solution at equilibrium

[Entanglement]

Say that we have a salt solution does the volume of the solution change after when the salt is ionized and equilibrium is achieved ??

 

[eigenperson]

I think what you're asking is whether Vol(salt) + Vol(water) = Vol(solution). The answer is no.

For sodium chloride and water, Vol(solution) < Vol(salt) + Vol(water). For other salts (e.g. lithium iodide) the opposite can occur. This absurdly long paper (it's paywalled, so go to a university library if you want to read it) gives data for the alkali metal halides.