JEE Main 2026 · ChemistryNumerical answerNumerical valueMediumMulti-step

JEE Main 4 April 2026, Shift 1, Chemistry Q75

Question 75 of 75 in this shift, Chemistry question 25 of 25, Section B.

A non-volatile, non-electrolyte solid solute when dissolved in

40

g of a solvent, the vapour pressure of the solvent decreased from

760

mm Hg to

750

mm Hg. If the same solution boils at

320

K, then the number of moles of the solvent present in the solution is ______. (Nearest integer) [Given: boiling point of the pure solvent

=319.5

K_b

of the solvent

=0.3\ \mathrm{K\ kg\ mol^{-1}}

]

Official answer

NTA final key.

Chapter: Solutions
Topic: Colligative Properties
Idea tested: Boiling Point Elevation

Same idea in other shifts

Asked 13× in all

8 Apr 2026, Shift 2 · Q54Which of the following statements are not correct ? A. For water, magnitude of $\mathrm{K_b}$ is more than the magnitude of…MediumOtherHas a figure
2 Apr 2025, Shift 2 · Q73When 1 g each of compounds AB and $\mathrm{AB_2}$ are dissolved in 15 g of water separately, they increased the boiling point of water by…MediumNumerical value
3 Apr 2025, Shift 1 · Q542 moles each of ethylene glycol and glucose are dissolved in 500 g of water. The boiling point of the resulting solution is: (Given :…EasySingle correct
4 Apr 2024, Shift 1 · Q842.5 g of a non-volatile, non-electrolyte is dissolved in 100 g of water at 25°C. The solution showed a boiling point elevation by 2°C.…MediumNumerical value
13 Apr 2023, Shift 2 · Q84Sea water contains 29.25% NaCl and 19% $\mathrm{MgCl_2}$ by weight of solution. The normal boiling point of the sea water is ______…MediumNumerical value
26 Jul 2022, Shift 2 · Q84The elevation in boiling point for 1 molal solution of non-volatile solute A is 3 K. The depression in freezing point for 2 molal solution…EasyNumerical value
27 Jul 2022, Shift 1 · Q65Boiling point of a 2% aqueous solution of a non-volatile solute A is equal to the boiling point of 8% aqueous solution of a non-volatile…EasySingle correct
27 Jun 2022, Shift 1 · Q832 g of a non-volatile non-electrolyte solute is disolved in 200 g of two different solvents A and B whose ebullioscopic constants are in…EasyNumerical value

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.