Liquid Solution

Solutions \(A, B, C\) and \(D\) are respectively 0.2 M urea, \(0.10 \mathrm{~M} \mathrm{~NaCl}, 0.05 \mathrm{~M} \mathrm{~BaCl}_2\) and 0.05 M \(\mathrm{AlCl}_3\). All solutions are isotonic with each other except