NEET2004Chemistrys Block ElementsActual
Which of the following is only acidic in nature?
Options
- ABe ( OH )₂
- BMg ( OH )₂
- CB ( OH )₃
- DAl ( OH )₃
Correct answer
C. B ( OH )₃
Step-by-step solution
B ( OH )₃ in aqueous medium coordinates a molecule of water to form the hydrated species In this species, B ³⁺ ion, because of its small size, exercises a high polarizing power thereby pulling the sigma electron charge of the coordinated O atom towards itself. The coordinated oxygen, in turn, pulls the sigma electron charge of the OH bond of the attached H ₂ O molecule towards itself. This facilitates the removal of H ⁺ ion from the O - H bond, as shown below. Thus the solution of B ( OH )₃ in water acts as a weak