JEE Main 2023 · ChemistryMultiple choiceSingle correctEasyCalculation

JEE Main 10 April 2023, Shift 1, Chemistry Q61

Question 61 of 90 in this shift, Chemistry question 1 of 30, Section A.

The number of molecules and moles in 2.8375 litres of

\mathrm{O_2}

at STP are respectively

(1) $1.505 \times 10^{23}$ and $0.250$ mol
(2) $7.527 \times 10^{23}$ and $0.125$ mol
(3) $7.527 \times 10^{22}$ and $0.125$ molOfficial answer
(4) $7.527 \times 10^{22}$ and $0.250$ mol

Official answer

Option 3

NTA final key.

Chapter: Some Basic Concepts of Chemistry
Topic: Mole Concept
Idea tested: Mole and Avogadro Calculations

Same idea in other shifts

Asked 11× in all

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25 Jun 2022, Shift 1 · Q81The number of N atoms in 681 g of $\mathrm{C_7H_5N_3O_6}$ is $x \times 10^{21}$ . The value of $x$ is __________. (…EasyNumerical value
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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.