JEE Main 2022 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 26 July 2022, Shift 1, Chemistry Q81

Question 81 of 90 in this shift, Chemistry question 21 of 30, Section B.

Chlorophyll extracted from the crushed green leaves was dissolved in water to make 2 L solution of Mg of concentration 48 ppm. The number of atoms of Mg in this solution is

x \times 10^{20}

atoms. The value of

x

is __________. (Nearest Integer) (Given : Atomic mass of Mg is 24 g mol

^{-1}

;

\mathrm{N_A} = 6.02 \times 10^{23}

mol

^{-1}

)

Official answer

NTA final key.

Chapter: Some Basic Concepts of Chemistry
Topic: Mole Concept
Idea tested: PPM and Mass Percentage

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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.