Question

How many sigma bonds are present in the molecule of dicyanoethene $(\mathrm{CN}-\mathrm{CH}=\mathrm{CH}-\mathrm{CN})$?

• A. $2$ sigma bonds
• B. $3$ sigma bonds
• C. $5$ sigma bonds
• D. $7$sigma bonds

Answer 1

The correct option is D

$7$sigma bonds

The explanation for the correct option:

Option (D): $7$

1. The sigma bond is the strongest covalent link formed by the head-on overlapping atomic orbitals.
2. Sigma bonds are found in alkanes, alkenes, and alkynes.
3. A double is composed of one sigma and one pi bond.
4. A triple bond is composed of one sigma bond and two pi bonds.
5. The structure of dicyanoethene is $\mathrm{N}\equiv \mathrm{C}-\mathrm{CH}=\mathrm{CH}-\mathrm{C}\equiv \mathrm{N}$
6. We can see that there are $7$ sigma bonds present in$\mathrm{CN}-\mathrm{CH}=\mathrm{CH}-\mathrm{CN}$.