What did Bohr Contribute to the Theory of an Atom Bohr’s model of an atomIn 1912, Niels Bohr put forward a model to explain the structure of an atom. The main postulates of the model are:An atom is made up of three particles : electons, protons and neutrons. Electrons have negative charge, protons have positive charge whereas neutrons have no charge, they are … [Read more...] about What did Bohr Contribute to the Theory of an Atom