Question

Assertion The highest oxidation state of $Os$ is $+8$.
Reason Osmium is a $5$ $d$-block element.

• A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion.
• B. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
• C. Assertion is true but Reason is false.
• D. Both Assertion and Reason are false.

Answer 1

Answer: (B)

Osmium has the electronic configuration $5d^{6}6s^2.$ As $5d$ and $6s$ are close in energy.
All the $8$ electrons can participate in bonding.