Carbon-hydrogen bond

Bond length

The length of the carbon-hydrogen bond varies slightly with the hybridisation of the carbon atom. A bond between a hydrogen atom and an sp hybridised carbon atom is about 0.6% shorter than between hydrogen and sp hybridised carbon. A bond between hydrogen and sp hybridised carbon is shorter still, about 3% shorter than sp C–H. This trend is illustrated by the molecular geometry of ethane, ethylene and acetylene.