The reaction between \(CaCl_2\) and \(MgSO_4\) in aqueous solution results in the formation of a white precipitate of \(CaSO_4\) and a solution of \(MgCl_2\). The balanced chemical equation for this reaction is:

$$CaCl_2(aq) + MgSO_4(aq) → CaSO_4(s) + MgCl_2(aq)$$

The reaction occurs because \(CaSO_4\) is less soluble in water than either \(CaCl_2 \) or \(MgSO_4\). As a result, when the two solutions are mixed, the \(CaSO_4\) precipitates out of solution.