sp3 hybridized orbitals and sigma bonds | Structure and bonding | Organic chemistry | Khan Academy

About this video

• Video Title: sp3 hybridized orbitals and sigma bonds | Structure and bonding | Organic chemistry | Khan Academy
• Channel: Khan Academy
• Speakers: Sal Khan
• Duration: 00:16:23

Overview

This video explains the concept of sp3 hybridized orbitals, how they are formed from the mixing of s and p orbitals in carbon atoms, and their role in forming sigma bonds. It contrasts the theoretical electron configuration of carbon with its actual bonding behavior, leading to the formation of tetrahedral structures like methane, and defines sigma bonds as the strongest type of covalent bond resulting from direct orbital overlap.

Key takeaways

• Atomic Orbitals Review: The video begins by reviewing the basic atomic orbitals (1s, 2s, 2p) and how electrons fill them according to their energy levels and spin pairing rules.
• Carbon's Electron Configuration and Bonding: It explains carbon's electron configuration (1s²2s²2p²) and contrasts the expected bonding based on this configuration with its actual ability to form four bonds, as seen in methane (CH4).
• sp3 Hybridization: The concept of sp3 hybridization is introduced, where one 2s orbital and three 2p orbitals mix to form four equivalent sp3 hybrid orbitals. These orbitals have 25% s character and 75% p character.
• Tetrahedral Geometry: sp3 hybridized orbitals lead to a tetrahedral arrangement around the carbon atom, explaining the observed molecular geometry and bond angles (approximately 109.5°) in molecules like methane.
• Sigma Bonds: The video defines sigma (σ) bonds as the strongest type of covalent bond, formed by the direct, head-on overlap of atomic orbitals (including hybridized orbitals) along the internuclear axis.