Group 13 Elements: The Boron Family

${\mathrm{Al}}_2{\mathrm{O}}_3$ is amphoteric - explain with suitable examples.

Aluminium reacts with dil. ${\mathrm{HNO}}_3$ but not with conc. ${\mathrm{HNO}}_3$ - explain.

Explain the reactions of aluminium with acids.

Explain why the electronegativity of $\mathrm{Ga}, \mathrm{In}$ and $\mathrm{Tl}$ will not vary very much.

Give reason why Aluminium wire is used to make transmission cables.

Give reason why aluminium utensils should not be kept in water overnight.

Give reason

A mixture of dilute $\mathrm{NaOH}$ and aluminium pieces is used to open drain.

Give reason

Why conc. ${\mathrm{HNO}}_3$ can be transported in aluminium container.

What happens when hydrated alumina is treated with aqueous $\mathrm{NaOH}$ solution.

If $\mathrm{B}–\mathrm{Cl}$ bond has a dipole moment, explain why ${\mathrm{BCl}}_3$ molecule has zero dipole moment.

Suggest the reasons why the $\mathrm{B}-\mathrm{F}$ bond lengths in ${\mathrm{BF}}_3 (130 \mathrm{pm})$ and ${\mathrm{BF}}_4^{-} (143 \mathrm{pm})$ differ.

What are electron deficient compounds ? Is ${\mathrm{BCl}}_3$ an electron deficient species ? Explain.

Write reactions to justify the amphoteric nature of aluminium.

Write the structure of ${\mathrm{AlCl}}_3$ as a dimer.

Write the electronic configuration of group $13$ elements.

Write balanced equation for: 

${\mathrm{B}}_2{\mathrm{H}}_6 + {\mathrm{NH}}_3 \to$

Explain why atomic radius of $\mathrm{Ga}$ is less than that of $\mathrm{Al}$.

How do you explain higher stability of $\mathrm{TlCl}$?

Discuss the pattern of variation in the oxidation states of Boron to Thalium.