NTA Abhyas NEET2020Chemistryp Block Elements (Group 13 & 14)Practice
The correct statement about orthoboric acid is
Options
- AIt is a strong monobasic acid
- BIt is not a proton donor, but a weak Lewis acid
- CIt is a tribasic acid
- DIt is harmful for eyes
Correct answer
B. It is not a proton donor, but a weak Lewis acid
Step-by-step solution
Orthoboric acid is a weak mono basic acid with K a =1.0 x 10 -9 . It does not act as protonic acid (i.e. proton donor) but behaves as Lewis acid by accepting a pair of electrons from OH - ion. B OH 3 + 2 H - O - H → B OH 4 - + H 3 O +