The mass of an electron is approximately 9.11 x 10-31 kilograms, which is incredibly small compared to protons and neutrons that make up the nucleus of an atom. In terms of charge, an electron carries a negative charge of about -1.602 x 10-19 coulombs. This negative charge is what allows electrons to interact with protons, which are positively charged, and thus helps to hold the atom together.
Electrons are primarily located in the outer regions of an atom, specifically in areas called electron shells or orbitals. These are not fixed paths but rather zones where electrons are likely to be found. The arrangement of electrons in these shells governs how an atom interacts with other atoms, playing a crucial role in chemical bonding and reactions.