The atoms in a single bond can rotate about the internuclear...

Name: Problem 12, Chapter 9: Chemistry
Uploaded: 2019-08-01T15:14:25-08:00
Duration: 3 min 49 s
Channel: Teesta Dasgupta
Description: The atoms in a single bond can rotate about the internuclear axis without breaking the bond. The atoms in a double and triple bond cannot rotate about the internuclear axis unless the bond is broken. Why?

The atoms in a single bond can rotate about the internuclear axis without breaking the bond. The atoms in a double and triple bond cannot rotate about the internuclear axis unless the bond is broken. Why?

Labs

Want to see this concept in action?

NEW

Explore this concept interactively to see how it behaves as you change inputs.

View Labs

Key Concepts

Sigma Bonds

Sigma bonds result from the head-on overlap of atomic orbitals, leading to electron density that is symmetrically distributed around the internuclear axis. This cylindrical symmetry allows the bonded atoms to rotate freely about the bond axis because the overlap remains effective regardless of the atoms' relative orientation.

Pi Bonds

Pi bonds are formed by the lateral overlap of p orbitals that are oriented above and below the plane of the nuclei. This type of overlap is highly directional and dependent on the orientation of the orbitals; therefore, any rotation about the bond axis would disrupt the pi overlap, effectively breaking the bond unless the rotation occurs with bond breaking.

Orbital Overlap and Bonding Constraints

The nature and geometry of orbital overlap dictate the bonding characteristics and constraints in molecules. While sigma bonds, due to their cylindrical symmetry, allow for rotational freedom, the fixed alignment required for pi bonds creates a rigid structure in multiple bonds, restricting rotation without bond disruption.

Transcript

Please give Ace some feedback