JEE Main 2021 · ChemistryNumerical answerNumerical valueEasyCalculation

JEE Main 17 March 2021, Shift 2, Chemistry Q51

Question 51 of 90 in this shift, Chemistry question 21 of 30, Section B.

The number of chlorine atoms in 20 mL of chlorine gas at STP is __________

10^{21}

. (Round off to the Nearest Integer). [Assume chlorine is an ideal gas at STP

R = 0.083\ \mathrm{L\ bar\ mol^{-1}\ K^{-1}}

\mathrm{N_A} = 6.023 \times 10^{23}

]

Official answer

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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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.