Calculate the proportion of O₂ and N₂ dissolved in water at 298 K. When air containing 20% O₂ and 80% N₂ by volume is in equilibrium with it at 1 atm pressure. Henry’s law constants for two gases are K_H(O₂) = 4.6 x 10⁴ atm and K_H (N₂) = 8.5 x 10⁴ atm.

Calculate the mole fractions of benzene and naphthalene in the vapour phase when an ideal liquid solution is formed by mixing 128 g of naphthalene with 39 g of benzene. It is given that the vapour pressure of pure benzene is 50.71 mm Hg and the vapour pressure of pure naphthalene is 32.06 mmHg at 300 K.

2.56 g of Sulphur is dissolved in 100g of carbon disulphide. The solution boils at 319. 692 K. What is the molecular formula of Sulphur in solution The boiling point of CS₂ is 319. 450K. Given that K_b for CS₂ = 2.42 K Kg mol^-1.

Henry’s law constant for solubility of methane in benzene is 4.2 x 10^-5 mm Hg at a particular constant temperature At this temperature.
Calculate the solubility of methane at
i) 750 mm Hg
ii) 840 mm Hg

The vapour pressure of pure benzene (C₆H₆) at a given temperature is 640 mm Hg. 2.2 g of non-volatile solute is added to 40 g of benzene. The vapour pressure of the solution is 600 mm Hg. Calculate the molar mass of the solute ?