A 0.1 molal aqueous solution of a weak acid HA freezes at -0.208°C. Assuming the acid to be 25% ionized, calculate the apparent molecular weight of the acid in solution. ($K_f$ for water = 1.86 K kg mol⁻¹)

A certain substance ‘A’ tetramerises in water to the extent of 80%. A solution of 2.5 g of A in 100 g of water lowers the freezing point by $0.3^\circ C$. The molar mass of A is

0.2 molal aqueous solution of a monobasic acid is 60% ionised. If Kb for water is $0.52\,K\,kg\,mo{l^{ - 1}}$ then the boiling point of the solution will be

A 0.1 molal aqueous solution of a weak acid HA freezes at -0.208°C. Assuming the acid to be 25% ionized, calculate the apparent molecular weight of the acid in solution. ($K_f$ for water = 1.86 K kg mol⁻¹)

A substance is completely trimerised on dissolution in a solvent. The van’t Hoff factor (i) for such change is :

A sample of a volatile liquid was vaporized in a Victor Meyer's apparatus at 100°C and 750 mmHg pressure. The volume of air collected over water at 25°C was 30 mL. The atmospheric pressure is 760 mmHg and the aqueous tension at 25°C is 24 mmHg. If the mass of the liquid taken was 0.06 g, what is the approximate molar mass of the liquid?

The observed molar mass of benzoic acid in benzene is higher than its normal molar mass. This is primarily due to:

The vapour density of undecomposed ${{\rm{N}}_2}{{\rm{O}}_4}$ is 46. When heated, vapour density decreases to 24.5 due to its dissociation to ${\rm{N}}{{\rm{O}}_2}.$ The per cent dissociation of ${{\rm{N}}_2}{{\rm{O}}_4}$ at the final temperature is :

When 10 g of a non-volatile solute is dissolved in 100 g of benzene, it raises boiling point by $1^\circ C$ then molecular mass of the solute is $({k_b}\;for\;{{\rm{C}}_6}{{\rm{H}}_6} = 2.53\;{\rm{kg}} - {\rm{mo}}{{\rm{l}}^{ - 1}})$

A sample of a compound has an observed molar mass that is twice its expected value. What is the most likely explanation for this?

The experimental molecular weight of an electrolyte will always be less than its calculated value because the value of van’t Hoff factor, ‘i’ is :