When a ionic compound like $\ce{NaCl}$ dissolves, it doesn't always full dissociate due to ionic pairing. This is measured by the van 't Hoff factor. Now, this is what I'm looking at for my chem experiment - how does ionic pairing affect freezing point depression. With changing radius the ionic pairing should change, and hence the van 't Hoff factor and freezing point depression should vary. Is this a valid hypothesis?
If so, my main issue lies with what solvents does ionic pairing occur in? Does it occur in all 3 of polar protic, polar aprotic and non polar solvents? I'm having trouble deciding which type of solvent to use. I was initially modelling water, but now I don't know how solvent type affects ionic association. Any help is appreciated. I'm not sure if ionic pairing occurs at all in all 3 types of solvents.