In the structure of $B_2H_6$,the number of $BH_2$ groups present in one plane,and the number of $B-H$ terminal bonds,$B-B$ bonds,and $B-H-B$ bridge bonds are respectively:

Borax is converted into crystalline boron by the following steps :
$Borax$ $\xrightarrow{HCl} (X)$ $\xrightarrow{\Delta} B_2O_3$ $\xrightarrow{\Delta, Y} B$
Identify $X$ and $Y$ respectively.

Select the correct statements from the following:
$A$) Aluminium liberates $H_2$ gas with dil. $HCl$ but not with aqueous $NaOH$.
$B$) Formula of sodium metaborate is $Na_3BO_3$.
$C$) Boric acid is a weak monobasic acid.
$D$) For thallium,$+1$ state is more stable than $+3$ state.

Which of the following compounds of boron does not exist in the free form?

Aluminium reacts with $NaOH$ and forms compound '$X$'. If the coordination number of aluminium in '$X$' is $6$,the correct formula of $X$ is:

The incorrect statement from the following for borazine is: