# What is the oxidation state of C in K_2CO_3?

Oct 10, 2016

Carbon clearly has an oxidation state of $+ I V$ in carbonate dianion.

#### Explanation:

The sum of the oxidation numbers always gives the charge on the ion. Carbonate anion is $C {O}_{3}^{2 -}$. Now oxygen generally has an oxidation number of $- 2$, and it does here.

Thus $- 2 = {C}^{\text{ON}} - 2 - 2 - 2$

So, clearly ${C}^{\text{ON}} = + I V$.

What is the oxidation number of carbon in oxalate dianion, ""^(-)O_2C-CO_2^-?