Question

Choose two of the following scientists: Anton Lavoisier, John Dalton, JJ Thomson, Robert Millikan, Ernest Rutherford, James Chadwick, & Niels Bohr. Describe their experiments and discoveries. Tell how that changed the atomic theory.

Answer 1

John Dalton:

John Dalton was the scientist who introduced atomic theory in the field of chemistry. Dalton worked on different gases and formulated this theory. The main points of Dalton's theory are:

• Every element present is made up of atoms.
• Atoms of an elements are have the same same properties whereas these properties are different for each element.
• According to his theory, an atom could not be broken down.
• Different atoms combine or get separated from each other during a chemical reaction.

Ernest Rutherford:

Ernest Rutherford is known as the father of nuclear physics due to his impressing research work on radioactivity of atoms. Rutherford was the first scientist to discover the nucleus of an atom and prove that the nucleus was charged. He also described that the electrons circle around the nucleus of an atom.