Question

Maximum oxidation state exhibited by osmium is:

• A. $+8$
• B. $+7$
• C. $+6$
• D. $+5$

Answer 1

The correct option is A $+8$

Osmium - $\left[Xe\right]4f^{14}5d^{6}6s^2$.
It can lose 8 electrons to form +8 oxidation state. In $Os{O}_4$, Osmium shows +8 oxidation state.