Final answer:
James Chadwick discovered the neutron in 1932 at the Cavendish Laboratory in Cambridge, England, using a nuclear reaction between beryllium and helium-4. His experiment confirmed that neutrons have a mass equal to a proton but no charge. This discovery earned him the 1935 Nobel Prize in Physics.
Step-by-step explanation:
James Chadwick discovered the neutron in 1932, and this groundbreaking experiment took place at the Cavendish Laboratory in Cambridge, England. By observing the nuclear reaction between beryllium (Be) and helium-4 (4He), which produced previously unknown neutral particles alongside carbon-12 (ยน2C), Chadwick was able to confirm the existence of neutrons. Through his meticulous work measuring velocities, he concluded that these particles had a mass comparable to that of protons but no electrical charge.
This landmark discovery added the neutron to the model of the atom as a fundamental subatomic particle necessary for atomic stability and nuclear reactions. Chadwick's research was instrumental to the scientific community and earned him the Nobel Prize in Physics in 1935. This finding was a pivotal moment in the field of nuclear physics and set the stage for future atomic and subatomic research.