# A solution containing 30 g of non-volatile solute exactly in 90 g of water has a vapour pressure of 2.8 kPa at 298 K. Further, 18 g of water is then added to the solution and the new vapour pressure becomes 2.9 kPa at 298 K. What will be the molar mass of the solute P and vapour pressure of water at 298 K (respectively) ?

$34gmole^{-1}$
Hence (B) is the correct answer.