Sir James Chadwick & his Contribution to Science Annalise S. Lydia V. Eddie R.

1911 Rutherford 1897 Thomson 1913 Bohr 1932 Chadwick 1926 Schrödinger -He shot alpha particles through gold foil; some bounced back - Introduced nucleus -Quantum mechanics -introduces subshells -”shells” are actually “orbitals” 1897 Thomson -Plum Pudding Model -introduces protons & electrons 1913 Bohr -Basis for our modern atomic model - Introduced electron shells 1932 Chadwick -introduced neutrons -lead to invention of atomic bombs 1926 Schrödinger

What Lead to a Change in the Previous Model Chadwick questioned how the believed theory (electrons were bound in the nucleus to cancel the charge of protons) was possible.

Previous Model the atom was believed to be composed of a positively charged nucleus surrounded by negatively charged electrons

The Experiment bombarded beryllium atoms with alpha particles and an unknown radiation was produced Chadwick interpreted this radiation as being composed of particles with a neutral electrical charge and the approximate mass of a proton He used scattered data to calculate the mass of this neutral particle He called this a neutron

New Model the atom is now believed to have neutrally charged particles called neutrons which add to atomic mass

Neato Thingos His hobbies included gardening and fishing Worked on Manhattan Project by the name of James Chaffee Absolute legend Jimmy Neutron was named in his honour During World War I, he was a prisoner of war in the Zivilgefangenenlager, Ruhleben, Germany Without him, the atomic bomb would not exist Neato Thingos