Question

Hans Bethe (prominent nuclear physicist) once remarked that he considered everything before 1932 “the prehistory of nuclear physics, and from1932 the history of nuclear physics.” The difference he said was the discovery of the neutron. Explain why?

Answer 1

Discovery of Nuetron -Jmame Chadick - 1932 - Opened up subject of Nuclear Physics, with applications of Radio Activity, Nuclear fission.

At this stage only Protons and Electrons were known, and they completed the Electrical Charge picture of atom and Nucleus.

Nuetron Explained the structure and mass of an atomic nucleus.

Nuetron being charge free allowed Physicists to collide it with Nuclei easily unlike alpha partcles which were +vely charged and hence repelled by Protons

It explained presence of various isotopes of elements and their radioactivity. It also explained why atoms with same chemical properties but variable weights of atoms.

Nuetrons helped in breaking heavy nuclei into smaller nuclei , thus releasing fission energy.