Chapter 13, Problem 79QP

Indicate which compound in each of the following pairs is more likely to form ion pairs in water: $\left(\text{a}\right){\text{ NaCl or Na}}_{\text{2}}{\text{S0}}_{\text{4}}\text{, }\left(\text{b}\right){\text{ MgCl}}_{\text{2}}{\text{or MgS0}}_{\text{4}}\text{, }\left(\text{c}\right)\text{ LiBr or KBr}\text{.}$