Trigonal pyramidal is a molecular shape that results when there are three bonds and one lone pair on the central atom in the molecule. Molecules with an tetrahedral electron pair geometries have sp3 hybridization at the central atom. Ammonia (NH3) is a trigonal pyramidal molecule.
Generalic, Eni. "Trigonal pyramidal molecular geometry." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. 28 Mar. 2025. <https://glossary.periodni.com>.
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