JEE Main 2020 · ChemistryMultiple choiceSingle correctEasyApplication

JEE Main 6 September 2020, Shift 2, Chemistry Q43

Question 43 of 75 in this shift, Chemistry question 18 of 25.

A set of solutions is prepared using 180 g of water as a solvent and 10 g of different non-volatile solutes A, B and C. The relative lowering of vapour pressure in the presence of these solutes are in the order [Given, molar mass of A = 100 g mol

^{-1}

; B = 200 g mol

^{-1}

; C = 10,000 g mol

^{-1}

]

(1) $A>B>C$ Official answer
(2) $B>C>A$
(3) $C>B>A$
(4) $A>C>B$

Official answer

Option 1

NTA final key (Sep 2020).

Chapter: Solutions
Topic: Colligative Properties
Idea tested: Relative Lowering of VP

Same idea in other shifts

Asked 12× in all

6 Apr 2026, Shift 1 · Q56When 0.25 moles of a non-volatile, non-ionizable solute was dissolved in 1 mole of a solvent the vapor pressure of solution was $x$ % of…EasySingle correct
2 Apr 2025, Shift 1 · Q55A solution is made by mixing one mole of volatile liquid A with 3 moles of volatile liquid B. The vapour pressure of pure A is 200 mm Hg…MediumSingle correct
7 Apr 2025, Shift 2 · Q55Liquid A and B form an ideal solution. The vapour pressures of pure liquids A and B are 350 and 750 mm Hg respectively at the same…MediumSingle correct
9 Apr 2024, Shift 2 · Q84The vapor pressure of pure benzene and methyl benzene at $27^\circ$ C is given as 80 Torr and 24 Torr, respectively. The mole fraction of…MediumNumerical value
6 Apr 2023, Shift 1 · Q85Mass of Urea ( $\mathrm{NH_2CONH_2}$ ) required to be dissolved in 1000 g of water in order to reduce the vapour pressure of water by 25% is…MediumNumerical value
11 Apr 2023, Shift 2 · Q62What weight of glucose must be dissolved in 100 g of water to lower the vapour pressure by 0.20 mm Hg ? (Assume dilute solution is being…MediumSingle correct
15 Apr 2023, Shift 1 · Q83The vapour pressure of 30% (w/v) aqueous solution of glucose is __________ mm Hg at $25^\circ\mathrm{C}$ . [Given : The density of 30%…MediumNumerical value
28 Jun 2022, Shift 1 · Q85The vapour pressures of two volatile liquids A and B at 25°C are 50 Torr and 100 Torr, respectively. If the liquid mixture contains 0.3…MediumNumerical 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.