Q. Carbonic acid is a

1420 220 The p-Block Elements Report Error

A

Weak tribasic acid

B

Weak dibasic acid

C

Strong tribasic acid

D

Strong dibasic acid

Solution:

Carbon dioxide on reaction with water gives a weak dibasic acid called carbonic acid which dissociates as
$H_{2} C O_{3} (a q) + H_{2} O (l) H C O_{3}^{-} (a q) + H_{3} O^{+} (a q)$
$H C O_{3}^{-} (a q) + H_{2} O (l) C O_{3}^{2 -} (a q) + H_{3} O^{+} (a q)$
It is called dibasic because it has two hydrogen ions to donate to a base in an acid base reaction