Question

Out of Valence bond theory, VSEPR Theory and molecular orbital theory, which have been found by scientists to be correct? Explain with reasons (5 mark question)

Answer 1

A major discovery based on molecular orbital theory is that it correctly explains that O2 has unpaired electrons (is paramagnetic), whereas valence bond theory thinks O2 has all paired electrons

Limitations of Valence Bond Theory

It fails to explain the tetravalency of carbon.

This theory does not discuss the electrons’ energies.

The assumptions are about the electrons being localized to specific locations.