In $IIIA$ group, $Tl$ (thalium) shows $+1$ oxidation state while other members show $+3$ oxidation state. Why
Presence of lone pair of electron in $Tl$
Inert pair effect
Large ionic radius of $Tl$ ion
None of these
The number of $2-$ centre $-2-$ electron and $3-$ centre $-2-$ electron bonds in $B_2H_6$, respectively, are
An element $A$ dissolves both in acid and alkali. It is an example of
The purification of alumina is called
Boric acid is an acid because its molecule
Give name of group $13$ elements.