Hybridization of Acetylene (C₂H₂) - sp

Q: What is the hybridization of Acetylene?

Acetylene (C₂H₂) is sp hybridized with Linear geometry and 180 degree bond angles.

What is the hybridization of Acetylene (C₂H₂)?

The central atom in Acetylene (C₂H₂) is sp hybridized. This produces Linear geometry with bond angles of 180 degrees. It has 2 hybrid orbitals and 2 unhybridized p orbitals (pi bond).

Formula	C₂H₂
Name	Acetylene
Hybridization	sp
Geometry	Linear
Bond Angle	180°
Hybrid Orbitals	2
Unhybridized p Orbitals	2pᵧ (pi bond), 2pᵩ (pi bond)

Introduction

Acetylene (C₂H₂) has a C≡C triple bond — one σ bond and two π bonds. Each carbon is sp hybridized with two leftover p orbitals for π bonding.

Electron Configuration

Carbon has 4 valence electrons: 2s² 2p². For a triple bond, carbon mixes only 2 orbitals, leaving 2 p orbitals unhybridized for the two π bonds.

Atomic Orbitals

The 2s orbital is spherical. The 2pₓ lies along the bond axis. The 2pᵧ and 2pᵩ orbitals are perpendicular and remain unhybridized.

Orbital Mixing

One s and one p orbital combine to form two sp hybrids pointing in opposite directions. Two p orbitals stay unchanged for π bonding.

Result

Two sp orbitals at 180° (linear). Two unhybridized p orbitals remain perpendicular to the bond axis and perpendicular to each other.

Bonding

The sp orbitals form σ bonds (one to H, one to the other C). The two unhybridized p orbitals on each carbon overlap to form two π bonds, completing the triple bond.

Interactive hybridization explorer with step-by-step orbital mixing animations for 8 molecules.

Visualize Acetylene's Orbital Mixing in 3D