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

Options

A. If both (A) and (R) are correct, but (R) is not the correct explanation of (A).
B. If both (A) and (R) are correct, but (R) is not the correct explanation of (A)
C. If (A) is correct, but (R) is incorrect.
D. If both (A) and (R) are incorrect.

Answer

B

Explanation

The electronic configuration of Os is `[Xe] 6s^(2) 4f^(14)5d^(6) 6s^(2)`. It has 8 electrons in the valence shell `(5d^(6) 6s^(2))` . It has the highest oxidation state of+8.