Easy INTEGER +4 / -1 PYQ · JEE Mains 2025

The molarity of a $70 \%$ (mass/mass) aqueous solution of a monobasic acid (X) is _________ $\times 10^{-1}$ M (Nearest integer)

[Given: Density of aqueous solution of (X) is $1.25 \mathrm{~g} \mathrm{~mL}^{-1}$

Molar mass of the acid is $70 \mathrm{~g} \mathrm{~mol}^{-1}$ ]

Answer (integer) 125

Solution

<p>Assuming 100 gm solution contain 70 gm solute.</p> <p>Volume of 100 gm solution will be $\frac{100}{1.25} \mathrm{ml}$.</p> <p>Molarity $=\frac{70 / 70}{100 / 1.25} \times 1000=12.5$ or $125 \times 10^{-1}$</p>

About this question

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

This question is part of PrepWiser's free JEE Main question bank. 163 more solved questions on Some Basic Concepts of Chemistry are available — start with the harder ones if your accuracy is >70%.

Drill 25 more like these. Every day. Free.

PrepWiser turns these solved questions into a daily practice loop. Chapter-wise drills, full mocks, AI doubt chat. No auto-renew.

Start free →