A solution has 1 : 4 mole ratio of pentane to hexane. The vapour pressure of the pure hydrocarbons at 20^oC are 440 mm of Hg for pentane and  120 mm of Hg for hexane. The mole fraction of pentane in the vapour phase would be

The better concentration term when the amount of solute is very small is

Out of the following which is not a colligative property?

The vapour pressure, at a given temperature, of an ideal solution containing 0.2 mole of a non volatile solute and 0.8 mole of solvent is 60 mm of Hg. The vapour pressure of the pure solvent at the same temperature is

A solution of urea (mol.mass 56 g mol^-1) boils at 100.18^oC at the atmosphere pressure. If kf and kb for water are 1.86 and 0.51 2 K kg mol^-1 respectively, the above solution will freeze at.

 Which one is a colligative property?

Which of the following 0.10 M aqueous solutions will have the lowest freezing point?

A solution contains non- volatile solute of molecular mass, M₂. Which of the following can be used to calculate the molecular mass of solute in terms of osmotic pressure?

A 5% solution of cane sugar (Molecular weight = 342 u) is isotonic with 1% solution of a substance X. The molecular weight of X is

The vapour pressure of a solvent decreased by 10 mm in two columns of mercury when a non-volatile solute was added to the solvent. The mole fraction of the solute in the solution is 0.2. What should be the mole fraction of the solvent if the decrease in the vapour pressure is to be 20mm of mercury?