JEE Mains JEE Advance BITSAT
JEE Mains | PYQ

Year

All years 2025 2024 2023

The percentage dissociation of a salt \( (\mathrm{MX_3}) \) solution at given temperature (van’t Hoff factor \( i = 2 \)) is ________ \( \% \) . (Nearest integer)

What is the freezing point depression constant of a solvent, \( 50 \, \mathrm{g} \) of which contain \( 1 \, \mathrm{g} \) non-volatile solute (molar mass \( 256 \, \mathrm{g\,mol^{-1}} \)) and the decrease in freezing point is \( 0.40 \, \mathrm{K} \)?

An organic compound weighing \( 500 \, \mathrm{mg} \), produced \( 220 \, \mathrm{mg} \) of \( \mathrm{CO_2} \), on complete combustion. The percentage composition of carbon in the compound is ________ \( \% \). (nearest integer). (Given molar mass in \( \mathrm{g \, mol^{-1}} \) of \( \mathrm{C}: 12, \, \mathrm{O}: 16 \))

Propane molecule on chlorination under photochemical condition gives two di-chloro products, “x” and “y”. Amongst “x” and “y”, “x” is an optically active molecule. How many tri-chloro products (consider only structural isomers) will be obtained from “x” when it is further treated with chlorine under the photochemical condition?

If \( \mathrm{A_2B} \) is \( 30\% \) ionised in an aqueous solution, then the value of van’t Hoff factor \( (i) \) is ______ \( \times 10^{-1} \).

\(1.24\, \text{g}\) of \(\mathrm{AX}_2\) (molar mass \(124\, \text{g mol}^{-1}\)) is dissolved in \(1\, \text{kg}\) of water to form a solution with boiling point of \(100.0156^\circ \text{C}\), while \(25.4\, \text{g}\) of \(\mathrm{AY}_2\) (molar mass \(250\, \text{g mol}^{-1}\)) in \(2\, \text{kg}\) of water constitutes a solution with a boiling point of \(100.0260^\circ \text{C}\).
\(K_b(\mathrm{H_2O}) = 0.52\, \text{K kg mol}^{-1}\)
Which of the following is correct?

Thyroxine, the hormone has given below structure.

The percentage of iodine in thyroxine is ________ \( \% \). (Nearest integer)
(Given molar mass in \( \mathrm{g \, mol^{-1}} \) \( \mathrm{C}: 12; \, \mathrm{H}: 1; \, \mathrm{O}: 16; \, \mathrm{N}: 14; \, \mathrm{I}: 127 \))

Consider the given plots of vapour pressure (\( \mathrm{VP} \)) vs temperature (\( T/K \)). Which amongst the following options is correct graphical representation showing \( \Delta T_f \), depression in the freezing point of a solvent in a solution?

Which of the following binary mixture does not show the behaviour of minimum boiling azeotropes?

Arrange the following solutions in order of their increasing boiling points.
(i) \( 10^{-4} \, \text{M} \) NaCl
(ii) \( 10^{-4} \, \text{M} \) Urea
(iii) \( 10^{-3} \, \text{M} \) NaCl
(iv) \( 10^{-2} \, \text{M} \) NaCl

Question 1 of 10Next →

JEE MAIN 2025 7th April Morning Shift

The percentage dissociation of a salt \( (\mathrm{MX_3}) \) solution at given temperature (van’t Hoff factor \( i = 2 \)) is ________ \( \% \) . (Nearest integer)