The relative lowering of the vapour pressure of an aqueous solution containing a nonvolatile solute is 0.0125. The molality of the solution is

Step-by-step solution

As we know p o - p p o = x 1 = mole fraction of solute The ratio p o - p p o is the relative lowering of vapour pressure, which is equal to 0.0125 here. So X 1 = 0.0125 The relation between the mole fraction and molality is 1 X 1 - 1 = 1000 m × 18 (molecular weight of H 2 O = 18 ) or 1 0.0125 - 1 = 100 m × 18 w m = 0.70 m