1. The neutron particles were isolated by Chadwick and contained a neutral electrical charge. When was this discovered in relation to other scientist's atomic hypotheses?

After Rutherford but before Thomson
Before Thomson but after Bohr
Before Bohr and Rutherford
After Thomson and Rutherford

1 answer

James Chadwick discovered the neutron in 1932. This discovery came after Ernest Rutherford’s nuclear model of the atom, which was proposed in 1911, and following J.J. Thomson’s discovery of the electron in 1897. Chadwick's work provided further insight into the structure of atoms by revealing the existence of a neutral particle in the nucleus.

Given this timeline, the correct choice from your options is:

After Thomson and Rutherford.