Question

Valency of carbon in ${{CO}_3}^{2-}$ ion is:

• A. 2
• B. 3
• C. 4
• D. 5

Answer 1

Answer: (C)

4

Valency of carbon in $C{O}_3^{2-}$ ion

Let the valency of carbon be $x$

$\therefore C{O}_3=-2$ [Overall charge is $-2$]

$\therefore x+3\times (-2)=-2$ [Charge on oxygen atom is $-2$]

$\therefore x-6=-2$ $\downarrow$

$\therefore x=-2+6$ [Electrons per shell of oxygen$⟶2,6$]

$\therefore x=+4$ It gains $2$ electrons from other atom to complete octet. Hence, has $-2$ valency.

Valency of Carbon in $C{O}_3^{2-}$ is $4$.