The oxidation of chromium in Cr2O7−2?

The oxidation of chromium in Cr₂O₇⁻²?

A. +4
B. +5
C. +6
D. +7

Correct Answer:

Option C = +6

Explanation

2 atoms of Cr,

7 X -2 atoms of O

2Cr – 14 = -2

2Cr = -2 + 14

2Cr = 12

Cr = 6