JEE Main Solutions Practice Questions With Solutions

Boiling point of a $2\mathrm{\%}$2 \% aqueous solution of a non-volatile solute A is equal to the boiling point of $8\mathrm{\%}$8 \% aqueous solution of a non-volatile solute B. The relation between molecular weights of A and B is

Two solutions A and B are prepared by dissolving 1 g of non-volatile solutes X and Y, respectively in 1 kg of water. The ratio of depression in freezing points for A and B is found to be 1 : 4. The ratio of molar masses of X and Y is

The depression in freezing point observed for a formic acid solution of concentration $0.5\mathrm{mL}{\mathrm{L}}^{-1}$0.5 \textrm{ } mL \left(\textrm{ } L\right)^{- 1} is ${0.0405}^{\circ }\mathrm{C}$0.0405^{\circ} C. Density of formic acid is $1.05\mathrm{g}{\mathrm{mL}}^{-1}$1.05 \textrm{ } g \left(\textrm{ } mL\right)^{- 1}. The Van't Hoff factor of the formic acid solution is nearly : (Given for water ${\mathrm{k}}_{\mathrm{f}}=1.86\mathrm{k}\mathrm{kg}{\mathrm{mol}}^{-1}$k_{f} = 1.86 k kg mol^{- 1} )

For a solution of the gases A, B, C and D in water at 298 K, the values of Henry's law constant (K_H) are 30.40, 2.34, 1.56 $\times$\times 10^$-$-5 and 0.513 k bar respectively. In the given graph, the lines marked as 'p' and 's' correspond respectively to :

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A) : At 10${}^{\circ }$^{\circ}C, the density of a 5 M solution of KCl [atomic masses of K & Cl are 39 & 35.5 g mol^$-$-1 respectively], is 'x' g ml^$-$-1. The solution is cooled to $-$-21${}^{\circ }$^{\circ}C. The molality of the solution will remain unchanged.

Reason (R) : The molality of a solution does not change with temperature as mass remains unaffected with temperature.

In the light of the above statements, choose the correct answer from the options given below :

Solute A associates in water. When 0.7 g of solute A is dissolved in 42.0 g of water, it depresses the freezing point by 0.2${}^{\circ }$^{\circ}C. The percentage association of solute A in water, is :

[Given : Molar mass of A = 93 g mol^$-$-1. Molal depression constant of water is 1.86 K kg mol^$-$-1.]