At a certain temperature, the vapor pressure of water is 50 mm. The relative lowering of vapor pressure of a solution containing 36 g of Glucose in 900 g of water is

The relation between the relative lowering of vapor pressure and mole fraction of solute is:

The relative lowering of vapor pressure is the same as the mole fraction of solute

the solute is glucose

moles = mass / molar mass

Calculating the moles of both solute and solvent we get

The moles of solute = 36 / 180 =0.2

The moles of water = 900 / 18 = 50

total moles =50.2

mole fraction of glucose = 0.2/50.2=0.004

thus the relative lowering of vapour pressure is 0.004