A 0.5 M aqueous $H_2SO_4$ solution is diluted from 2 litres to 20 litres. The concentration of the resulting solution will be
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 0.1 N
Use the dilution formula:
$M_1V_1 = M_2V_2$
Then convert molarity (M) to normality (N) using:
$N = M \times n$
where $n$ = basicity (number of replaceable ${H}^+$). For $\text{H}_2\text{SO}_4$, $\mathbf{n = 2}$.
Step Solution
Initial molarity $M_1 = 0.5 \, M$
Initial volume $V_1 = 2 \, L$
Final volume $V_2 = 20 \, L$
$M_2 = \frac{M_1V_1}{V_2} = \frac{0.5 \times 2}{20} = \frac{1}{20} = 0.05 \, M$
Convert to Normality:
$N = M \times 2 = 0.05 \times 2 = 0.1 \, N$