Single, Double and Triple Covalent Bonds

Single, double and triple covalent bonds differ from each other in the following ways.

• Single bond is formed by the sharing of one electron pair, (two electrons); a double bond is formed by the sharing of two electron pairs, (four electrons), whereas a triple bond involves sharing of three electron pairs, (six electrons).

• The bond lengths follow the order:

Triple bond length < Double bond length < Single bond length

In a triple bond, six electrons attract the nuclei with greater force, out of the three types of bond length. This decreases the distance of separation between the two nuclei the most. In a double bond, because of a larger distance of separation between the two nuclei than a triple bond, the four electrons attract the nuclei with a relatively lesser force. In a single bond, two electrons hold the nuclei with a still lesser force giving the largest length of bond. Since, a shorter bond means greater bond strength hence, the energy required to separate the bonded atoms (called bond energy) follows the order.

Triple bond > Double bond > Single bond.