Easy INTEGER +4 / -1 PYQ · JEE Mains 2020

6.023 $\times$ 1022 molecules are present in 10 g of a substance 'x'. The molarity of a solution containing 5 g of substance 'x' in 2 L solution is _____ × 10-3

Answer (integer) 25

Solution

Mass of 6.023 × 10<sup>22</sup> molecules of a substance = 10 g <br><br>Mass of 6.023 × 10<sup>23</sup> molecules of the substance = 100 g <br><br>$\therefore$ Molar mass of the substance = 100 g mol<sup>–1</sup> <br><br>Molarity of the solution = <span style="display: inline-block;vertical-align: middle;"> <div style="text-align: center;border-bottom: 1px solid black;">moles of solute</div> <div style="text-align: center;">volume of solution(in l)</div> </span> <br><br>= ${{\left( {5/100} \right)} \over 2}$ = 0.025

About this question

Subject: Chemistry · Chapter: Some Basic Concepts of Chemistry · Topic: Mole Concept

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