Question

Assign oxidation numbers to the underlined elements in the following species:

CaO₂

Answer 1

CaO₂

+2	x
Ca	O2

Then, we have

(+2) + 2(x) = 0

⇒ 2 + 2x = 0

⇒ x = -1

Hence, the oxidation number of O is - 1.