A solution of urea in water has a boiling point of 373.128 K. Calculate the freezing point of the same solution. [Given: For water, K _f = 1.86 Km^-1, K_b = 0.52 Km^-1]

3

(a)

0.1 mole of acetic acid was dissolved in 1 kg of benzene. Depression in freezing point of benzene was determined to be 0.256 K. what conclusion can you draw about the state of the solute in solution? [Given: K_f for benzene = 5.12 K/m]

3

(a)

A 0.1539 molal aqueous solution of cane sugar (mol. mass = 342 g mol ^-1) has a freezing point of 271 K while the freezing point of pure water is 273.15 K. what will be the freezing point of an aqueous solution containing 5 g of glucose (mol. mass = 180 g mol^-1) per 100 g of solution?

3

(a)

The vapour pressure of water is 12.3 kPa at 300 K. Calculate vapour pressure of 1 molal solution of a non-volatile solute in it.

3

(a)

What role does the molecular interaction play in solution of alcohol and water?

3

(a)

An aqueous solution of 2% non-volatile solute exerts a pressure of 1.004 bar at the normal boiling point of the solvent. What is the molecular mass of the solute?

3

(a)

A mongst the following compounds, identify which are insoluble, partially soluble in water?
(i) phenol , (ii) toluene,
(iii) formic acid, (iv) ethylene glycol,
(v) chloroform, (vi) pentanol.

3

(a)

100 g of liquid A (molar mass 140 g mol ^-1) was dissolved in 1000 g of liquid B (molar mass 180 g mol^-1). The vapour pressure of pure liquid B was found to be 500 torr. Calculate the vapour pressure of pure liquid A and its vapour pressure in the solution if the total vapour pressure of the solution is  475 torr.

3

(a)

A solution of sucrose (Mol. Wt. 342) is prepared by dissolving 68.4 g of it per litre of solution. What is osmotic pressure at 300 K? (R = 0.0821 L atm K^-1 mol^-1)

3

(a)

An aqueous solution of 3.12 g of BaCl₂ in 250 g of water is found to boil at 100.0832^oC. Calculate the degree of dissociation of BaCl₂. [K _b (H₂O) = 0.52 K/m.]

3

(a)

A person suffering from high blood pressure is advised to take minimum quantity of common salt. Give reason.

3

(a)

A) Why the vapour pressure of a solution of glucose in water lower than that of water?
B) 0.1 molal solution of glucose and NaCl respectively. Which one will have higher boiling point?

3

(a)

How can you remove the hard calcium carbonate layer of the egg without damaging its semi-permeable membrane? Can this egg be inserted into a bottle with a narrow neck without distorting its shape? Explain the process involved.

3

(a)

Calculate the boiling point of a 1M aqueous solution (density 1.04 g mL^-1) of potassium chloride (K_b for water = 0.52 K kg mol^-1, Atomic masses : K = 39 u, CI = 35.5 u). Assume, potassium chloride is completely dissociated in solution.

3

(a)