Geometries, preferred, VSEPR prediction

Comment (a) The 1 ion is one of the few structures for which the bond angle (180°) can be predicted accurately even though the central atom contains lone pairs, (b) In C2H4, all six atoms lie in the same plane. The overall planar geometry is not predicted by the VSEPR model, but we will see why the molecule prefers to be planar later. In reality, the angles are close, but not equal, to 120° because the bonds are not all equivalent. 

The preferred geometries of carbenium ions and carbanions are correctly predicted by the valence shell electron pair repulsion (VSEPR) theory. The theory is general and can be applied to organic and inorganic compounds, regardless of charge. 

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