Protons are positively charged and the lightest subatomic particle. Neutrons have no charge and are the lightest subatomic particle. The mass of the neutron nearly equals the mass of a proton.
An electron is nearly massless. It has a rest mass of 9.1×10-28 gram, which is only 0.0005 the mass of a proton. The electron reacts only by the electromagnetic, weak, and gravitational forces; it does not respond to the short-range strong nuclear force that acts between quarks and binds protons and neutrons in the atomic nucleus. The electron has an antimatter counterpart called the positron. This antiparticle has precisely the same mass and spin, but it carries a positive charge. If it meets an electron, both are annihilated in a burst of energy. Positrons are rare on the Earth, being produced only in high-energy processes (e.g., by cosmic rays) and live only for brief intervals before annihilation by electrons that abound everywhere.
Under ordinary conditions, electrons are bound to the positively charged nuclei of atoms by the attraction between opposite electric charges. In a neutral atom the number of electrons is identical to the number of positive charges on the nucleus. Any atom, however, may have more or fewer electrons than positive charges and thus be negatively or positively charged as a whole; these charged atoms are known as ions. Not all electrons are associated with atoms. Some occur in a free state with ions in the form of matter known as plasma.
The electron was the first subatomic particle discovered. It was identified in 1897 by the British physicist J.J. Thomson during investigations of cathode rays. The discovery of electrons as the ultimate carriers of electricity not only established the materialistic origin of electricity but also opened up a whole new vista for our microscopic understanding of the flow of electricity. Not all electrons are associated with atoms. Some occur in a free state with ions in the form of matter known as plasma.
Electrons – The lightest subatomic particle is the electron at 9.11×1031 kg. It is almost massless in comparison to protons and neutrons and behaves like both a wave and a particle. The electron is one of the lightest subatomic particles and one of the key components of atoms, along with neutrons and protons.
The number of electrons in an atom is equal to the number of protons and this is called the atomic number Z. The atomic number is the number of protons in the atom. Each element has its own unique atomic properties. Electrons have an electric charge of -1, which is equal but opposite to the charge of a proton, which is +1
FAQ
Which subatomic particle is the heaviest?
Which is the lightest particle electron or alpha?
