`2B(OH)_(3) + 2NaOHhArr NaBO_(2) + Na[B(OH)_(4)]+2H_(2)O`
How can this reaction be made to proceed in forwards direction ?

Options

A. Addition of cis 1, 2 diol
B. Addition of borax
C. Addition of trans 1, 2 diol
D. Addition of `Na_2 HPO_4`

Answer

A

Explanation

`B(OH)_3` is a weak mono basic acid but act as a strong acid in presence of polyhydroxy compounds. Now the solution can be titrated with NaOH and end point is diluted using an indicator.
So the added compound must be cis 1, 2 diol to enhance the acidic property. It forms very stable complex with `[B(OH)_4]^-` formed in forward direction (as `Na[B(OH)_4]`)

Thus it effectively removes `Na[B(OH)_4]` from the solution. Hence by Le–Chatelier’s principle, reaction proceeds in forward direction.