Give reasons for the following :
(a) When 2g of benzoic acid is dissolved in 25 g of benzene, the experimentally determined molar mass is always greater than the true value.
(b) Mixture of ethanol and acetone shows positive deviation from Raoult's Law.
(c) The preservation of fruits by adding concentrated sugar solution protects against bacterial action.

The experimentally determined molar mass for what type ofsubstances is always lower than the true value when water is used as solvent. Explain. Give one example of such a substance and one example of a substance which does not show a large variation from the true value.

The experimentally determined molar mass for what type ofsubstances is always lower than the true value when water is used as solvent. Explain. Give one example of such a substance and one example of a substance which does not show a large variation from the true value.

Which of the following statement is/are correct about acetone and trichloromethane mixture? a) Mixtures of acetone and trichloromethane show positive deviation from Raoult's law b) The forces of attaction acting between molecules of acetone and trichoromethene in a mixture are stronger then those acting between the molecules in pure acetone c) Pure acetone can be obtained by the careful fractional distillation of any mixture of acetone and trichloromethane d) When acetone and trichoromethane are mixed, the enthapy change negative

2g of benzoic acid ( C_6H_5COOH ) is dissolved in 25g of benzene show depression in freezing point equal to 1.62K. Molar depression constant for benzene, K_f =4.9K kg mol^-1 . What is percentage association of acid if it forms a dimer in solution?

Answer the questions (given below) which are based on the following diagram ? Consider some facts about the above phase diagram. Vapour pressure diagram for real solutions of two liquids A and B that exhibit a positive deviation from Raoult's law. The vapour presssure of both A and B are greater than predicted by Raoult's law. The dashed lines represented the plots for ideal solutions. A : This is obserbed when A...B attractions are greater than average of A...B and B.....B attraction : B : DeltaH_(mix) = +ve, DeltaV_(mix) = +ve C : Boiling point is smaller than expected such that vaporisation is increased D : Mixture can from azeotropic mixture Select correct facts.

Answer the question (given below) which are based on the following diagra. Consider some facts about the above phase diagram : Vapour pressure diagram for real solutions of two liquids A and B that exhibit a positive deviation from Raoult's law. The vapour pressure of both A and B are greater than predicted by Raoult's law. The dashed lines lines represented the plots for ideal solutions. A : This is observed when A...B attraction are greater than average of A...B and B...B attraction: B : DeltaH_("mix")=+ve,DeltaV_("mix")=+ve C : Boiling point is smaller than expected such that vaporisation is increased D : Mixture is called azeotropic mixture Select correct facts

Answer the question (given below) which are based on the following diagra. Consider some facts about the above phase diagram : Vapour pressure diagram for real solutions of two liquids A and B that exhibit a positive deviation from Raoult's law. The vapour pressure of both A and B are greater than predicted by Raoult's law. The dashed lines lines represented the plots for ideal solutions. A : This is observed when A...B attraction are greater than average of A...B and B...B attraction: B : DeltaH_("mix")=+ve,DeltaV_("mix")=+ve C : Boiling point is smaller than expected such that vaporisation is increased D : Mixture is called azeotropic mixture Select correct facts

Which of the following solutions is expected to show positive deviations from Raoult's law? a)Pyridine-formic acid b)Ethanol-cyclohexane c)Acetone-chloroform d)Hydrochloric acid-water

2g of benzoic acid (C_(6)H_(5)COOH) dissolved in 25 g of benzene shows a depression in freezing point equal to 1.62 K. Molar depression constant for benzene is 4.9 K kg mol^-1 . What is the percentage association of acid if it forms double molecules (dimer) in solution ?