Electrons

The electron is a very small negatively charged (1.60x10^-19C) subatomic particle having a mass of 9.11x10^-28g. The electron is considered a point particle. It carries a charge in electrical circuits and forms the cloud of electrons around the nucleus of the atom; there are the same number of electrons associated with an atom as there are protons in its nucleus. The part played by the electron in the structure of the atom is best understood by first considering the Bohr atom.