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 $5 d^{6}\, 6 \,s^{2} .$ As $5 \,d$ and $6 \,s$ are close in energy.
All the $8$ electrons can participate in bonding.