Aluminium is usually found in $+3$ oxidation state. In contrast,thallium exists in $+1$ and $+3$ oxidation states. This is due to

White phosphorus reacts with thionyl chloride to give

Identify the correct set of $13^{th}$ group elements which do not form amphoteric oxides?

$A$ obtained by Ostwald's method involving air oxidation of $NH_3$,upon further air oxidation produces $B$. $B$ on hydration forms an oxoacid of Nitrogen along with evolution of $A$. The oxoacid also produces $A$ and gives positive brown ring test.

Phosphonic acid $(H_3PO_3)$ is:

The correct code for stability of oxidation states for given cations is:
$(i)$ $Pb^{2+} > Pb^{4+}, Tl^{+} < Tl^{3+}$
$(ii)$ $Bi^{3+} < Sb^{3+}, Sn^{2+} < Sn^{4+}$
$(iii)$ $Pb^{2+} > Pb^{4+}, Bi^{3+} > Bi^{5+}$
$(iv)$ $Tl^{3+} < In^{3+}, Sn^{2+} > Sn^{4+}$
$(v)$ $Sn^{2+} < Pb^{2+}, Sn^{4+} > Pb^{4+}$
$(vi)$ $Sn^{2+} < Pb^{2+}, Sn^{4+} < Pb^{4+}$