# Which one of the following aqueous solution will exhibit abnormal osmotic pressure?

$\begin{array}{1 1}(a)\;\text{magnesium sulphate}\\(b)\;\text{sucrose}\\(c)\;\text{urea}\\(d)\;\text{glucose}\end{array}$

Among all the given compounds, only $MgSO_4$ can dissociate into ions $Mg^{2+}$ and $SO_4^{2-}$
Hence (a) is the correct answer.
edited Jul 16, 2014