(a) State the following:
(i) Henry's law about partial pressure of gas in a mixture.
(ii) Raoult's law in its general form in reference to solutions.
(b) A solution prepared by dissolving 8.95 mg of a gene fragment in 35.0 ML of water has an osmotic pressure of 0.335 torr at 25^oC. Assuming gene fragment is non-electrolyte, determine its molar mass.

(a) Assuming complete ionization, calculate the expected freezing point of solution prepared by dissolving 6.00 g of Glauber's salt, Na₂SO₄. 10H₂O in 0.1 kg of H₂O. (K _f for H₂O = 1.86 K kg mol^-1) [At. mass of Na = 23, S = 32, O= 16, H = 1 u].
(b) Two liquids X and Y boil at 110 ^oC and 130 ^oC respectively. Which of them has higher vapor pressure at 50^oC ?

(a) Define Azeotropes and explain broefly minimum boiling azeotrope by taking suitable example.
(b) The vapour pressures of pure liquids A and B are 450 mm 700 mm of Hg respectively at 350 K. Calculate the composition of the liquid mixture if total vapour pressure is 600 mm of Hg. Also find the composition of the mixture in the vapour phase.

The elements A and B form purely covalent compounds having molecular formulae AB₂ and AB₄. When dissolved in 20g of benzene, 1g of AB₂ lowers the freezing point by 2.3K, whereas 1g of AB4 lowers it by 1.3K. the molal depression constant for benzene is 5.1 K kg/mol, calculate the atomic mass of A and atomic mass of B. (A=25.59, B=42.64).

a) Why constant boiling mixtures behave like a single component when subjected to distillation.
b) What type of Azeotropic mixtures are formed by the following solution
i) H₂O and HCl ii) H₂O and C₂H₅OH
c) Give one practical application of depression of freezing point?
d) A Solid solution is formed between two substances. One whose particles are very large and the other particles are very small. What type of solid solution is this likely to be?
e) Write the Raoults Law for each component of a binary solution and show that the total vapour pressure of the solution may be expressed as P = P⁰A + (P⁰B – P⁰A) X_B.

Vapour pressure of pure benzene at a certain temperature is 640 mm Hg. A non-volatile non-electrolyte solid weighing 2.175g is added to 39.0 of benzene. The vapour pressure of solution is 600 mm Hg. What is the molecular mass of solid substance? (65.9g mol^-1).

The degree of dissociation of Ca(NO₃ )₂ in dilute solution aqueous solution containing 7.0g of the solute per 100g of water at 100⁰ C is 70 percent. If the vapour pressure of water at 100⁰ C is 760mm, calculate the vapour pressure of the solution. (746.02mm).

What mass of a non-volatile solute urea (NH₂CONH₂) need to be dissolved in 100g of water in order to decrease the vapour pressure of water by 25%? also calculate the molality of the solution. (18.52m).

8.0575 X 10^-2 kg of Glauber’s salt is dissolved in water to obtain 1 dm³ of a solution of density 1077.2 kg m^-3. Calculate the molarity, molality & mole fraction of Na₂SO₄ in the solution. (0.2508m, 0.0045, 0.25M).