Hybridization of Water (H₂O) - sp3

Introduction

Water has a bent shape with a 104.5° bond angle. Oxygen has 6 valence electrons — it forms 2 bonds and holds 2 lone pairs. Hybridization explains why.

Electron Configuration

Oxygen has 6 valence electrons: 2s² 2p⁴. Two p orbitals are half-filled (for bonding) and the s orbital is full. But all four electron groups need equivalent orbitals.

Atomic Orbitals

The 2s orbital is a sphere. The three 2p orbitals are dumbbells along x, y, and z. Oxygen uses all four orbitals for its 2 bonds and 2 lone pairs.

Orbital Mixing

One s and three p orbitals mix to form four sp³ hybrids. Even though only two form bonds, all four orbitals are equivalent in shape.

Result

Four sp³ orbitals point roughly tetrahedrally. Two hold bonding pairs (toward H atoms), two hold lone pairs. The lone pairs compress the angle from 109.5° to 104.5°.

Bonding

The two bonding sp³ orbitals overlap with hydrogen 1s orbitals to form σ bonds. The lone pair orbitals are occupied but not bonded to anything.

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