The bond angles and hybridizations around carbon atoms in a molecule depend on the bonding geometries, which are determined by the type and number of bonds. Examples include 109.5° tetrahedral (sp³), 120° trigonal planar (sp²), and 180° linear (sp).
The bond angles and hybridization around carbon atoms labeled as ca, cb, and cc in a molecule depend on the number of bonds and the type of bonds they form. Typically:
- Tetrahedral geometries have bond angles of 109.5° and are characterized by sp³ hybridization.
- Trigonal planar geometries have bond angles of 120° and are characterized by sp² hybridization.
- Linear geometries have bond angles of 180° and are characterized by sp hybridization.
For example, in ethene (C2H4), the molecule is flat and the carbons are sp²-hybridized with a bond angle of 120°. In ethyne (C2H2), the carbons are part of a triple bond and are sp-hybridized with bond angles of 180°.