Chemistry

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(ii) 2, 2 and 3

Explanation: The van't Hoff factor's values are determined by the degree of dissociation. Strong electrolytes include KCl, NaCl, and K₂SO₄. When compared to KCl and NaCl, the extent or degree of dissociation with Na₂SO₄ is the largest. 

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(i) Two different solutions of sucrose of the same molality prepared in different solvents will have the same depression in freezing point.

Explanation: T_f = K_f m

The dip in freezing the point of the solution would not be the same since K_f values are dependent on the composition of the solvent.

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(i) Is higher than that at a dilute solution.

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(iv) It loses water due to osmosis.

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(iii) About three times

Explanation:  A colligative property is a decrease in freezing point. In the case of MgCl₂, the van't Hoff factor will be higher. When a molecule of MgCl₂ dissociates in its aqueous solution, it produces 3 ions. One molecule of 0.01M MgCl₂ produces three particles/ions in solution, resulting in a threefold increase in the number of particles present in the solution. As a result, the freezing point of 0.01M MgCl₂ will be three times lower than that of 0.01M glucose solution, because there will be no dissociation of the molecule.

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(i) Kkg mol^–1 or K (molality)^-1

(ii) 1.0 M Na₂SO₄

Explanation: When compared to the other three electrolytes, the van't Hoff factor in 1.0 M Na₂SO₄ solution is I > 1 and is the highest. As a result, when compared to the other electrolytes in their 1.0 M solutions, the extent of dissociation in the case of 1.0 M Na₂SO₄ would be the greatest, giving the greatest number of ions.

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(ii) The number of solute particles in solution.

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Option (ii) i.e., It has low concentration of oxidizing agents is the answer since the common components of photochemical smog are ozone, nitric oxide, acrolein, formaldehyde and peroxyacetyl nitrate (PAN). Photochemical smog causes serious health problems and both ozone and PAN act as powerful eye irritants. Photochemical smog contains high concentrations of oxidants. 

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(i) Methanol and acetone.

Explanation: The interaction (A-A)* is greater than the interaction (A-B)*. Methanol has greater intermolecular hydrogen bonding than methanol and acetone combined. As a result, methanol and acetone mixes will deviate from Raoult's law in a favourable way. The (A-A)* interaction is the interaction of acetone particles/molecules that do not have any hydrogen bonds between them.

The interaction between the particles / molecules of acetone and methanol is known as the (A-B)* interaction.