Question

Aqueous solution of which of the following boron compounds will be strongly basic in nature?

• A. NaBH₄
• B. LiBH₄
• C. B₂H₆
• D. Na₂B₄O₇

Answer 1

The Correct Option is D

To determine which boron compound forms a strongly basic solution, we need to consider the chemistry of the compounds given in the options:

1. NaBH₄ (Sodium Borohydride):

   NaBH₄ is a well-known reducing agent and does not produce a basic solution in water.

2. LiBH₄ (Lithium Borohydride):

   Similar to NaBH₄, LiBH₄ is also primarily a reducing agent and does not form a basic aqueous solution.

3. B₂H₆ (Diborane):

   Diborane is a covalent hydride rather than an ionic compound and does not dissociate in water to form a basic solution.

4. Na₂B₄O₇ (Sodium Tetraborate or Borax):

   Na₂B₄O₇ is known as borax. When it dissolves in water, it hydrolyzes to form boric acid (H₃BO₃) and sodium hydroxide (NaOH), creating a basic solution:

   • The reaction in water: \[\text{Na}_{2}\text{B}_{4}\text{O}_{7} + 7 \text{H}_2\text{O} \rightarrow 2 \text{NaOH} + 4 \text{H}_3\text{BO}_3\]
   • The production of NaOH makes the solution basic.

Thus, the compound that makes the aqueous solution strongly basic is Na₂B₄O₇ (Sodium Tetraborate or Borax).

Correct Answer: Na₂B₄O₇