Question

The volume of $0.1\, M$ oxalic acid that can be completely oxidized by $20\, ml$ of $0.025 \, M \, KMnO_4$ solution is

• A. $125\, ml$
• B. $25 \,ml$
• C. $12.5\, ml$
• D. $37.5\, ml$

Answer 1

Answer: (C)

$12.5\, ml$

Answer 2

$N=\frac{\text { molecular weight }}{\text { equivalent weight }} \times M$
$N_{ KMnO _{4}}=\frac{158}{31.6} \times 0.025$
$=0.125$
$N_{ O.A. }=\frac{126}{63} \times 0.1=0.2$
$\because\,\,\, N_{1} V_{1}=N_{2} V_{2}$
$\therefore \,\,\, 0.2 \times V =0.125 \times 20$
$V =\frac{0.125 \times 20}{0.2}$
$=12.5 \,mL$