The Neutron Discovery Quiz

Rutherford's Prediction

• In 1920, Ernest Rutherford predicted the existence of a neutral particle within the atom, which he called the neutron.

Chadwick's Discovery

• In 1932, James Chadwick experimentally confirmed Rutherford's prediction.
• Chadwick bombarded a beryllium target with alpha particles, resulting in the emission of a neutral, highly penetrating radiation.
• This neutral radiation was later identified as neutrons.

Neutron Properties

• Neutrons are neutral particles, carrying no electrical charge.
• The mass of a neutron is approximately 1 atomic mass unit (amu), slightly heavier than a proton.

Mass Discrepancy

• Rutherford's observations showed that the atomic mass of an element was significantly greater than the combined mass of its protons, suggesting the presence of another particle.
• The mass of the proton alone could not account for the total mass of an atom, leading to the prediction and discovery of the neutron.