Question

What is the oxidation state of each individual carbon atom in ${\mathrm{C}}_2{{\mathrm{O}}_4}^{2-}$?

Answer 1

Step 1: Oxidation state:

• "Oxidation state of an element in a compound ascertained according to a set of rules formulated on the basis that electron pair in a covalent bond belongs entirely to a more electronegative element."

Step 2: Calculation for oxidation state in ${\mathrm{C}}_2{{\mathrm{O}}_4}^{2-}$:

• The overall charge on ${\mathrm{C}}_2{{\mathrm{O}}_4}^{2-}$is $-2$.
• Let "x" be the oxidation state of the Carbon atom:
• The oxidation state of Oxygen is $-2$.

$$\begin{gathered} \left(2\times \mathrm{x}\right)+(4\times -2)=-2 \\ 2\mathrm{x}-8=-2 \\ 2\mathrm{x}=-2+8 \\ 2\mathrm{x}=+6 \\ \mathrm{x}=\frac{6}{2} \\ \mathrm{x}=+3 \end{gathered}$$

Thus, the Oxidation state of each Carbon atom in ${\mathrm{C}}_2{{\mathrm{O}}_4}^{2-}$ is $+3$.