10 mL of 2 M NaOH solution is added to 20 mL of 1 M HCl solution kept in a beaker. Now, 10 mL of this mixture is poured into a volumetric flask of 100 mL containing 2 moles of HCl and made the volume upto the mark with distilled water. The solution in this flask is :
Solution
<p>When $10 \mathrm{ml}, 2 \mathrm{M} \mathrm{NaOH}$ solution is added to 20 ml of 1 M HCl solution :</p>
<p>$\mathrm{NaOH}+\mathrm{HCl} \rightarrow \mathrm{NaCl}+\mathrm{H}_2 \mathrm{O}$</p>
<p>$$\begin{array}{rlrl}
\text { Initial : MV } & =2 \times 0.1 & & M V=1 \times 0.2 \\
& =0.2 \text { mole } & & =0.2 \mathrm{~mole} \\
\text { Final } & 0 & 0
\end{array}$$</p>
<p>$\therefore$ Resulting solution becomes neutral.</p>
<p>Now when 10 mol of above solution is poured into a flask containing 2 mole HCl and made solution 100 ml will distilled water.</p>
<p>Molarity of $\mathrm{HCl}=\frac{2}{100} \times 1000=20$</p>
About this question
Subject: Chemistry · Chapter: Some Basic Concepts of Chemistry · Topic: Mole Concept
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