# 6.7.1: Practice Shape

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Exercise $$\PageIndex{1}$$

Give the electron geometry and the molecule geometry of PCl3.  (The Lewis structure was on a previous practice page.)

Electron geometry is tetrahedral (109.5° angle) because there are 4 electron regions around the central P atom.

Molecular geometry is pyramidal (also called trigonal pyramidal) because there are 3 atoms and 1 lone pair around the central P atom.

Exercise $$\PageIndex{1}$$

Give the electron geometry and the molecule geometry of H2O.

Electron geometry is tetrahedral (109.5° angle) because there are 4 electron regions around the central O atom.

Molecular geometry is bent because there are 2 atoms and 2 lone pairs around the central O atom.

Exercise $$\PageIndex{1}$$

Give the electron geometry and the molecule geometry of the nitrate ion (NO31–). (The Lewis structure was on a previous practice page.)