Explain the nature of boric acid as a Lewis acid in water. 

Given below are the statements about diborane.

$(a)$ Diborane is prepared by the oxidation of $\mathrm{NaBH}_{4}$ with $\mathrm{I}_{2}$.

$(b)$ Each boron atom is in sp $^{2}$ hybridized state.

$(c)$ Diborane has one bridged $3$ centre$-2-$electron bond.

$(d)$ Diborane is a planar molecule.

The option with correct statement(s) is :

Which among the following statement(s) is(are) true for the extraction of aluminium from bauxite?

$(A)$ Hydrated $Al _2 O _3$ precipitates, when $CO _2$ is bubbled through a solution of sodium aluminate.

$(B)$ Addition of $Na _3 AlF _6$ lowers the melting point of alumina.

$(C)$ $CO _2$ is evolved at the anode during electrolysis.

$(D)$ The cathode is a steel vessel with a lining of carbon.

$B{\left( {OH} \right)_3} + NaOH \to NaB{O_2} + Na\left[ {B{{\left( {OH} \right)}_4}} \right] + {H_2}O$ 

How can this reaction is made to proceed in forward direction?

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$.

Assertion $A$ : Boric acid is a weak acid

Reason $R$ : Boric acid is not able to release $H ^{+}$ion on its own. It receives $OH ^{-}$ion from water and releases $H ^{+}$ion.

In the light of the above statements, choose the most appropriate answer from the options given below.

The formation of molecular complex $BF_3 - NH_3$ results in a change in hybridization of boron