Easy INTEGER +4 / -1 PYQ · JEE Mains 2021

The mole fraction of a solute in a 100 molal aqueous solution is ___________ $\times$ 10$-$2. (Round off to the Nearest Integer).

[Given : Atomic masses : H : 1.0 u, O : 16.0 u ]

Answer (integer) 64

Solution

Let weight of H<sub>2</sub>O = 1000 g<br><br>Moles of solute = 100<br><br>(mole)H<sub>2</sub>O = ${{1000} \over {18}}$<br><br>Mole fraction of solute = ${{mole\,of\,solute} \over {Total\,moles}}$<br><br>$= {{100} \over {100 + {{1000} \over {18}}}} = {{1800} \over {2800}}$<br><br>${X_{solute}} = 64 \times {10^{ - 2}}$

About this question

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

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