The osmotic pressure of a dilute solution of an ionic compound XY in water is four times that of a solution of 0.01 M BaCl2 in water. Assuming complete dissociation of the given ionic compounds in water, the concentration of XY (in mol L–1 ) in solution is :
(1) 4 × 10–4
(2) 4 × 10–2
(3) 16 × 10–4
(4) 6 × 10–2
