The oxidation state +1 is more stable is thallium. Why?

Variability in the oxidation states of lanthanides is limited. Why?

+1 oxidation state is stable for the element

+1 oxidation state is stable for the element

+1 oxidation state is stable for the element

The stable oxidation state of Bismuth is

+2 oxidation state of lead is more stable than +4 , because of

(A) SnCl_(4) is more covalent than SnCl_(2) (R ) Compound with higher oxidation state of metal is more covalent than with lower oxidation state