1
JEE Main 2022 (Online) 27th July Evening Shift
Numerical
+4
-1

When a certain amount of solid A is dissolved in $$100 \mathrm{~g}$$ of water at $$25^{\circ} \mathrm{C}$$ to make a dilute solution, the vapour pressure of the solution is reduced to one-half of that of pure water. The vapour pressure of pure water is $$23.76 \,\mathrm{mmHg}$$. The number of moles of solute A added is _____________. (Nearest Integer)

2
JEE Main 2022 (Online) 26th July Evening Shift
Numerical
+4
-1

The elevation in boiling point for 1 molal solution of non-volatile solute A is $$3 \mathrm{~K}$$. The depression in freezing point for 2 molal solution of $$\mathrm{A}$$ in the same solvent is 6 $$K$$. The ratio of $$K_{b}$$ and $$K_{f}$$ i.e., $$K_{b} / K_{f}$$ is $$1: X$$. The value of $$X$$ is [nearest integer]

3
JEE Main 2022 (Online) 29th June Evening Shift
Numerical
+4
-1

Elevation in boiling point for 1.5 molal solution of glucose in water is 4 K. The depression in freezing point for 4.5 molal solution of glucose in water is 4 K. The ratio of molal elevation constant to molal depression constant (Kb/Kf) is _________.

4
JEE Main 2022 (Online) 29th June Morning Shift
Numerical
+4
-1

1.2 mL of acetic acid is dissolved in water to make 2.0 L of solution. The depression in freezing point observed for this strength of acid is 0.0198$$^\circ$$C. The percentage of dissociation of the acid is ___________. (Nearest integer)

[Given : Density of acetic acid is 1.02 g mL$$-$$1, Molar mass of acetic acid is 60 g mol$$-$$1, Kf(H2O) = 1.85 K kg mol$$-$$1]