Boron is unable to form $BF_{6}^{3-}$ ion. Explain.

Maximum number of atoms which are present in one plane of $H_3BO_3$?

Which of the following is $NOT$ true regarding the structure of diborane $(B_2H_6)$?

Which of the following reactions will yield the crystalline variety of boron?

Give uses of boron and its compounds.

Given below are two statements:
Statement $I$: Aluminium is more electropositive than thallium as the standard electrode potential value of $E^\circ_{Al^{3+}/Al}$ is negative and $E^\circ_{Tl^{3+}/Tl}$ is positive.
Statement $II$: The sum of first three ionization enthalpies of boron is very high when compared to that of aluminium. Due to this reason,boron forms covalent compounds only and aluminium forms $Al^{3+}$ ion.