The pyramidal molecular shape has three atoms bound to the central atom. The feature that results in the pyramidal shape is the unshared electron pair associated with the central atom. The bond angles in the pyramidal structure are generally around 109.5o.
Phosphorous trichloride (PCl3) is characterized by pyramidal molecular shape. It is composed of one phosphorous and three chlorine atoms. It contains also one unshared electron pair.
Molecular model of phosphorous trichloride
Structural formula of phosphorous trichloride
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