To neutralize completely 20 mL of 0.1M aqueous solution of phosphorus acid (H3PO3) the volumeof 0.1 M aqueous KOH solution required is

Question

To neutralize completely 20 mL of 0.1M aqueous solution of phosphorus acid (H3PO3) the volumeof 0.1 M aqueous KOH solution required is (A) 10 mL (B) 20 mL (C) 40 mL (D) 60 mL

Tardigrade Admin · Accepted Answer

H 3 PO 3 is a dibasic acid. H 3 PO 3+2 KOH longrightarrow K 2 HPO 3+2 H 2 O (MA VA/nA)=(MB VB/nB) (0.1 × 20/1)=(0.1 × VB/2) VB=40 mL

Q. To neutralize completely 20 mL of 0.1M aqueous solution of phosphorus acid $(H_{3} P O_{3})$ the volumeof 0.1 M aqueous KOH solution required is

10 mL

20 mL

40 mL

60 mL

$H_{3} P O_{3}$ is a dibasic acid.
$H_{3} P O_{3} + 2 K O H ⟶ K_{2} H P O_{3} + 2 H_{2} O$
$\frac{M _{A} V _{A}}{n _{A}} = \frac{M _{B} V _{B}}{n _{B}}$
$\frac{0.1 \times 20}{1} = \frac{0.1 \times V _{B}}{2}$
$V_{B} = 40 m L$

Q. To neutralize completely 20 mL of 0.1M aqueous solution of phosphorus acid (H3​PO3​) the volumeof 0.1 M aqueous KOH solution required is