Solutions

20 g hemoglobin in a 1 L aqueous solution (A) at 300 K is separated from pure water by semi permeable membrane. At equilibrium the height of solution in a tube dipped in a solution (A) is found to be 80.0 mm higher than the tube dipped in water. The molar mass of hemoglobin is kg mol-1. (Nearest integer) (Given : g = 10 m s-2, R = 8.3 kPa dm3 K-1 mol-1, density of solution = 1000 kg m-3)

A non-volatile, non-electrolyte solid solute when dissolved in 40 g of a solvent, the vapour pressure of the solvent decreased from 760 mm Hg to 750 mm Hg. If the same solution boils at 320 K, then the number of moles of the solvent present in the solution is . (Nearest integer) [Given: boiling point of the pure solvent = 319.5 K, Kb of the solvent = 0.3 K kg mol-1]

Two liquids A and B form an ideal solution. At 320 K, the vapour pressure of the solution, containing 3 mol of A and 1 mol of B is 500 mm Hg. At the same temperature, if 1 mol of A is further added to this solution, vapour pressure of the solution increases by 20 mm Hg. Vapour pressure (in mm Hg) of B in pure state is . (Nearest integer)

The osmotic pressure of a living cell is 12 atm at 300 K. The strength of sodium chloride solution that is isotonic with the living cell at this temperature is g L-1. (Nearest integer) Given : R = 0.08 L atm K-1 mol-1 Assume complete dissociation of NaCl (Given: Molar mass of Na and Cl are 23 and 35.5 g mol-1 respectively.)

A substance 'X' (1.5 g) dissolved in 150 g of a solvent 'Y' (molar mass = 300 g mol-1) led to an elevation of the boiling point by 0.5 K. The relative lowering in the vapour pressure of the solvent 'Y' is 10-2. (nearest integer) [Given: Kb of the solvent = 5.0 K kg mol-1] Assume the solution to be dilute and no association or dissociation of X takes place in solution.

The percentage dissociation of a salt (MX3) solution at given temperature (van't Hoff factor i = 2) is % (Nearest integer)

Sea water, which can be considered as a 6 molar (6 M) solution of NaCl, has a density of 2 g mL-1. The concentration of dissolved oxygen (O2) in sea water is 5.8 ppm. Then the concentration of dissolved oxygen (O2) in sea water, in terms of molality, is x 10-4 m. x = . (Nearest integer) Given: Molar mass of NaCl is 58.5 g mol-1 Molar mass of O2 is 32 g mol-1

When 1 g each of compounds AB and AB2 are dissolved in 15 g of water separately, they increased the boiling point of water by 2.7 K and 1.5 K respectively. The atomic mass of A (in amu) is 10-1 (Nearest integer) (Given : Molal boiling point elevation constant is 0.5 K kg mol-1)

If A2B is 30% ionised in an aqueous solution, then the value of van't Hoff factor (i) is 10-1.

The observed and normal molar masses of compound MX2 are 65.6 and 164 respectively. The percent degree of ionisation of MX2 is %. (Nearest integer)

Molarity (M) of an aqueous solution containing x g of anhyd. CuSO4 in 500 mL solution at 32 is 2 10-1 M. Its molality will be 10-3 m. (nearest integer). [Given density of the solution = 1.25 g/mL]

The vapor pressure of pure benzene and methyl benzene at 27 C is given as 80 Torr and 24 Torr, respectively. The mole fraction of methyl benzene in vapor phase, in equilibrium with an equimolar mixture of those two liquids (ideal solution) at the same temperature is 10-2 (nearest integer)

A solution containing 10 g of an electrolyte AB2 in 100 g of water boils at 100.52°C. The degree of ionization of the electrolyte ( ) is 10-1. (nearest integer) [Given : Molar mass of AB2 = 200 g mol-1, Kb (molal boiling point elevation const. of water) = 0.52 K kg mol-1, boiling point of water = 100°C; AB2 ionises as AB2 A2+ + 2B-]

A solution is prepared by adding 1 mole ethyl alcohol in 9 mole water. The mass percent of solute in the solution is (Integer answer) (Given : Molar mass in g mol-1 Ethyl alcohol : 46 water : 18)

Molality of an aqueous solution of urea is 4.44 m. Mole fraction of urea in solution is x 10-3, Value of x is . (Integer answer)

Consider the dissociation of the weak acid HX as given below HX(aq) H+(aq) + X-(aq), Ka = 1.2 10-5 [Ka : dissociation constant] The osmotic pressure of 0.03 M aqueous solution of HX at 300 K is 10-2 bar (nearest integer). [Given : R = 0.083 L bar mol-1 K-1]

When 'x' 10-2 mL methanol (molar mass = 32 g, density = 0.792 g/cm3) is added to 100 mL water (density = 1 g/cm3), the following diagram is obtained. [figure] x = (nearest integer). [Given : Molal freezing point depression constant of water at 273.15 K is 1.86 K kg mol-1]

An artificial cell is made by encapsulating 0.2 M glucose solution within a semipermeable membrane. The osmotic pressure developed when the artificial cell is placed within a 0.05 M solution of NaCl at 300 K is 10-1 bar. (nearest integer). [Given : R = 0.083 L bar mol-1 K-1] Assume complete dissociation of NaCl

Considering acetic acid dissociates in water, its dissociation constant is 6.25 10-5. If 5 mL of acetic acid is dissolved in 1 litre water, the solution will freeze at -x 10-2 C, provided pure water freezes at 0 C. x = . (Nearest integer) Given : (Kf)water = 1.86 K kg mol-1 density of acetic acid is 1.2 g mL-1. molar mass of water = 18 g mol-1. molar mass of acetic acid = 60 g mol-1. density of water = 1 g cm-3 Acetic acid dissociates as CH3COOH CH3COO + H

2.5 g of a non-volatile, non-electrolyte is dissolved in 100 g of water at 25 . The solution showed a boiling point elevation by 2 . Assuming the solute concentration is negligible with respect to the solvent concentration, the vapor pressure of the resulting aqueous solution is mm of Hg (nearest integer) [Given : Molal boiling point elevation constant of water (Kb) = 0.52 K kg mol-1, 1 atm pressure = 760 mm of Hg, molar mass of water = 18 g mol-1]

2.7 kg of each of water and acetic acid are mixed. The freezing point of the solution will be -x C. Consider the acetic acid does not dimerise in water, nor dissociates in water. x = (nearest integer) [Given: Molar mass of water = 18 g mol-1, acetic acid = 60 g mol-1 Kf H2O : 1.86 K kg mol-1 Kf acetic acid: 3.90 K kg mol-1 freezing point: H2O = 273 K, acetic acid = 290 K]

Mass of ethylene glycol (antifreeze) to be added to 18.6 kg of water to protect the freezing point at -24 is kg (Molar mass in g mol-1 for ethylene glycol 62, Kf of water = 1.86 K kg mol-1)

The osmotic pressure of a dilute solution is 7 105 Pa at 273 K. Osmotic pressure of the same solution at 283 K is 104 Nm-2.

Molality of 0.8 M H2SO4 solution (density 1.06 g cm-3) is 10-3 m.