Chemistry · Some Basic Concepts of Chemistry (Mole Concept) + Stoichiometry

JEE Main 2025 — 28 January, Evening Shift — Question 34

Concentrated nitric acid is labelled as $75 \%$ by mass. The volume in mL of the solution which contains 30 g of nitric acid is___.

Given : Density of nitric acid solution is $1.25 \mathrm{~g} / \mathrm{mL}$

Answer: C

$\% \mathrm{w} / \mathrm{w}$ of $\mathrm{HNO}_{3}=75 \%$

means 100 gm of solution containing 75 g of $\mathrm{HNO}_{3}$

$\&\left(\frac{\mathrm{gm}}{\mathrm{m}_{1}}\right)_{\text {solution }}=1.25=\frac{100 \mathrm{gm}}{\mathrm{V}}$

$\mathrm{V}_{\mathrm{ml}}$ of 100 gm solution $=\frac{100}{1.25} \mathrm{ml}$

$\because 75 \mathrm{gm}$ of $\mathrm{HNO}_{3}$ present in $\frac{100}{1.25} \mathrm{ml}$ solution

$\therefore 30 \mathrm{gm}$ of $\mathrm{HNO}_{3}$ present in $\frac{100}{1.25 \times 75} \times 30=32 \mathrm{ml} \text { solution }$

Answer key and solution verified before publishing.

Start with this question, then two more from the same chapter — with a tutor that explains every step. Free.