Ans: Neutrons are subatomic particles that are one of the primary constituents of atomic nuclei. They are represented by ‘n’ or ‘no’. Neutrons are chargeless. They do, however, have mass which is slightly greater in magnitude than that of a proton. Neutrons and protons are collectively referred to as nucleons, since they behave in a similar manner inside the nuclei of atoms. The mass of a neutron is approximately 1 atomic mass unit (abbreviated to amu). The branch of physics that deals with the study of the properties of neutrons and the interactions of these subatomic particles with other materials and electromagnetic radiation is called nuclear physics.

An element’s overall nuclear and chemical properties is usually determined by the total number of protons in its atomic nucleus (atomic number) and the total number of neutrons in its atomic nucleus (neutron number). The sum of the total number of protons and neutrons in the atomic nucleus yields the mass number of that atomic nucleus. It is important to note that different isotopes of the same element share the same atomic number but differ in their mass numbers (which implies that they all can contain the same number of protons but vary in the total number of neutrons that are present in their nuclei).

Discovery of Neutrons

The New Zealand born British physicist Ernest Rutherford first theorized neutrons in the year 1920.The discovery of neutrons is the credit of the British physicist James Chadwick (1932). He received the Nobel prize in physics for this discovery in the year 1935.

Charge and Mass of Neutrons

The neutron contains 0 amount of electric charge. So, neutrons are neutrally charged subatomic particles.
The mass of a neutron is 1.008 atomic mass units (approx.). When converted into kgs, the mass of the neutron is approximated to 1.674*10-27 kg.
Since neutrons lack electric charge, their mass cannot be directly determined via the analytical technique of mass spectrometry.

Properties of Neutrons

Despite the fact that the neutron is considered to be a neutral particle, the magnetic moment of neutrons is not equal to zero. Though electric fields have no effects on neutrons, they are affected by magnetic fields. The magnetic moment associated with the neutron can be considered as an indication of its quark substructure and the distribution of its internal charges. The neutron’s magnetic moment’s actual value was directly measured first at Berkeley, California, by Luis Alvarez and Felix Bloch (1940).