Solutions Question 216
Question: To neutralise completely 20 mL of 0.1 M aqueous solution of phosphorous acid $ (H_3PO_3), $ the volume of 0.1 M aqueous KOH solution required is [AIEEE 2004]
Options:
A) 40 mL
B) 20 mL
C) 10 mL
D) 60 mL
Show Answer
Answer:
Correct Answer: A
Solution:
$ H_3PO_3 $ is a dibasic acid $ N_1V_1 $ (acid) $ =N_2V_2 $ (base) $ 0.1\times 2\times 20=0.1\times 1\times V_2 $
$ \therefore $ $ V_2=\frac{0.1\times 2\times 20}{0.1\times 1}=40,ml $