Which of the following staments are incorrect in context of borax?

Options

A. It is made up of two triangular `BO_(3)` units and two tetrahederal `BO_(4)` units
B. One mole of bora can be used as a buffer
C. It is a useful primary standerd for titrating against acids
D. Aqueous solution of borax can be used as a buffer

Explanation

(b) Borax is `Na_(2)B_(4)O_(7)cdot10H_(2)O` in which 2 molecules of water among 10 molecules form a part of structure and exists as `Na_(2)[B_(4)O_(5)(OH)_(4)]cdot8H_(2)O`.
Methyl orange with pH value of 3.7 is used to detect end point. Aqueous solution of borax acts as buffer because borax is salt of strong base (NaOH) and weak acid `(H_(3)BO_(3))`