Question

The oxidation state of Cr in CrO₆ is ______.

Options

• +4

• −6

• +12

• +6

Answer 1

The oxidation state of Cr in CrO₆ is +6.

Explanation:

The value is +6 because CrO₆ contains two peroxide groups \[\ce{O^{2-}_2}\], where each of those four oxygen atoms has an oxidation state of −1. The remaining single oxygen atom has a normal oxidation state of −2. Cr + 4(−1) + 1(−2) = 0, which means Cr must be +6.