Intexte Questions Vapour pressure of pure water at 298 K is 23.8 mm Hg. 50 g of urea (NH,CONH,) is dissolved in 850 g of water. Calculate the vapour pressure of water for this solution and its relative lowering. Boiling point of water at 750 mm Hg is 99.63°C. How much sucrose is to be added to 500 g of water such that it boils at 100°C. 1 Calculate the mass of ascorbic acid (Vitamin C, C H20) to be dissolved in 75 g of acetic acid to lower its melting point by 1.5°C. K = 3.9 K kg mol 2 Calculate the osmotic pressure in pascals exerted by a solution prepared by dissolving 1.0 g of polymer of molar mass 185,000 in 450 ml of water at 37°C.