## 3g urea is dissolved in 45g of water. The relative lowering of vapour pressure is:

A) 0.05 B) 0.04 C) 0.02 D) 0.01 Solution Urea = Mass/ mol mass. 3/60. = 0.05 Water= Mass/ mol mass. 45/60. = 2.5 By relative lowering of vapour pressure ∆P/Po. =. X(water) 0.05/0.05+2.5 = 0.0196 = 0.02 is the answer

## The vapour pressures of two liquids A and B in their pure states are in the ratio of 1 : 2. A binary solution of A and B contains A and B in the mole proportion of 1 : 2. The mole fraction of A in the vapour phase of the solution will be:

A) 0.2 B) 0.25 C) 0.52 D) 0.33 Solution

## Which of the following is not a characteristic of a covalent compound

A) no definite compound B) Insoluble in polar solvent C) small difference in electronegativity D) Low melting point Solution Answer A No definite geometry is not a characteristic of a covalent compound. The covalent compound has definite geometrical shape, because of the bond forms.

## All colloidal dispersions have

A) low osmotic pressure B) No osmotic pressure C) High osmotic pressure D) Very High osmotic pressure Answer All colloidal dispersion have low osmotic pressure. The osmotic pressure is a colligative property and depends on the number of solute particles. If number of solute particles in solution is low, the osmotic pressure is low. So … Read more

## A solution of two liquids boils at a temperature more than the boiling point of either them.Hence, the binary solution shows

A) negative deviation from Raoult’s law B) positive deviation from Raoult’s law C) No deviation from Raoult’s law D) postive or negative deviation from Raoult’s law depends upon the composition Answer negative deviation from Raoult’s law

## 0.023g of sodium metal is reacted with 100cm 3 of water. The pH of the resulting solution is?

A) 10 B) 11 C) 9 D) 12 Solution

## Excess of carbon dioxide is passed through 50 mL, of 0.5 M calcium hydroxide solution. After the completion of the reaction, the solution was evaporated to dryness. The solid calcium carbonate was completely neutralised with 0.1 N hydrochloric acid. The volume of hydrochloric acid required is (Atomic mass of calcium = 40)

A) 300 cm3 B) 500 cm3 C) 290cm3 D) 450 cm3 Solution