The electron is a building block of the atom. Its
mass is 1836 times smaller than that of the proton and neutron.
The electron charge is negative and
is fixed to be 1.602,176,634×10-19 C.
The name is derived from the Greek word elektron (ἤλεκτρον), meaning "amber".
History
The existence of the electron was first demonstrated in 1897 by
the English physicist Joseph John Thomson (1856 - 1940).
