Question

Discuss how well VSEPR predicts shape, how shape contributes to chemical reactivity, and how computer modeling can help support your predictions.

Answer 1

VSEPR theory is a set of procedures for predicting the molecular geometry of a molecule using the information contained in the molecule’s Lewis structure. The central concept of VSEPR theory is that electron pairs in the valence shell of an atom adopt an arrangement in space that minimizes the repulsions between the like charged (all negative) electron pairs. The specific arrangement adopted by the electron pairs depends on the number of electron pairs present.

The valence shell electron pairs orient themselves such that there is miniumu repulsions and maximum stablitty.

The exact geometry depends upon the no of electron pairs in the moclecule. The non bonded electron pairs distort the geometry from ideal expected geometry.

Two electron pairs, to be as far apart as possible from one another, are found on opposite sides of a nucleus—that is, at 180^o angles to one another . Such an electron pair arrangement is said to be linear.

similarly we can predict the shape for different molecules.

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Computer modelling please post separately...Thanks