Question

What is the oxidation state of Cr in Cr2O7^-2 ​

Answer 1

Answer:

The sum of the oxidation numbers in Cr2O72-, a polyatomic ion, is -2, the charge of the ion. There are seven oxygen atoms, so the total charge is − 2⋅7 = − 14. So, a chromium atom here has an oxidation number of + 6.

hence the answer is +6

Answer 2

Oxidation state of Cr in Cr₂O₇⁻² is +6

Explanation:

Oxidation state of Cr :-

Let x be the oxidation state of Cr in  Cr₂O₇⁻²

we have to find the value of x

In Cr₂O₇⁻²

⇒(2× x ) + 7× (-2 )= -2

⇒ 2x -14 = -2

⇒ x =  +6

Therefore the oxidation state of   Cr₂O₇⁻² ​ is +6