Question

The number and type of bonds in $C_2^{2-}$ ion in $Ca{C}_2$ are :

• A. one $\sigma$ bond and one $\pi$-bond
• B. one $\sigma$ bond and two $\pi$-bonds
• C. two $\sigma$ bonds and two $\pi$ -bonds
• D. two $\sigma$ bonds and one $\pi$ - bond

Answer 1

The correct option is B one $\sigma$ bond and two $\pi$-bonds

$C_2^{2-}$ ion $⟶$ $[C\equiv C{]}^{2-}$

Dicarbide ion $C_2^{2-}$ has 1 sigma and 2 pi bonds. There are two $\pi$ bonds and one $\sigma$ bond in a triple bond.

Hence, the correct option is $\left(B\right)$.