Question

The number and type of bonds between two carbons atoms in $Ca{C}_2$ are

• A. One sigma(s) and one pi(p) bonds
• B. One sigma (s) bond and two pi (p) bonds
• C. One sigma (s) bond and one and a half pi (p) bonds
• D. One sigma (s) bond

Answer 1

The correct option is B One sigma (s) bond and two pi (p) bonds

$Ca{C}_2$ is an ionic species. It's made of $C{a}^{2+}$ and ${C_2}^{2-}$

We need to figure out the type of bonds between carbons in ${C_2}^{2-}$

With simple logic of elimination, we can say that there should be a triple bond between the carbons.

If there was a triple bond, the structure would be as follows -