σ-bonds, π-bonds, and Hybridization

Types of Covalent Bonding

How it Works

During hybridization, one s orbital and p orbital(s) combine to form hybrid orbitals, with the quantity depending on the type of hybridization (sp, sp², sp³). 

Each hybrid orbital is asymmetrical in shape, with a smaller lobe (more s character) that points toward the nucleus, and a larger lobe (more p character) that points away from the nucleus. 

sp hybridization - 1 s orbital + 1 p orbital, four electrons total. This creates one pair of sp orbitals, creating a linear electron geometry. 

sp² hybridization - 1 s orbital + 2 p orbital, six electrons total. This creates three sp orbitals, creating a trigonal planar electron geometry. 

sp³ hybridization - 1 s orbital + 3 p orbital, eight electrons total. This creates four sp orbitals, creating a tetrahedral electron geometry. 

Example: Methane (CH₄)

A carbon atom has the electron configuration 1s², 2s², 2p². It needs four valence electrons to form four single bonds with hydrogen atoms to create methane, but only the two (unpaired) electrons of the 2p subshell are currently available. 

First, one 2s electron jumps to an empty 2p orbital, creating the excited-state configuration of 1s², 2s¹, 2p³.

Next, the one 2s and three 2p orbitals undergo sp³ hybridization, forming four equivalent hybrid orbitals. These orbitals will automatically arrange to form a tetrahedral shape, and due to each of them possessing an unpaired electron, allow carbon to form σ-bonds with four hydrogen atoms by overlapping with their 1s orbitals.