Question #e4bba
1 Answer
Jul 21, 2015
A species contains an equal number of sigma and pi bonds if it contains the same number of single and triple bonds.
Explanation:
A double bond always contains one σ bond and one π bond.
So the number of double bonds doesn't matter.
They always contribute an equal number of σ and π bonds, no matter how many double bonds there are.
A single bond has one σ bond, while a triple bond has one σ and two π bonds.
So each single bond-triple bond pair has two σ bonds and two π bonds.
Few molecules have exactly the same number of σ and π bonds.
Some that I can think of are:
carbon dioxide:
carbon suboxide:
sulfur cyanide:
tetracyanoethylene:
