Which of the following statements about the electron is incorrect?
(a) It is a negatively charged particle.
(b) The mass of electron is equal to the mass of neutron.
(c) It is a basic constituent of all atoms.
(d) It is a constituent of cathode rays.
The answer is the option (b)
The mass of electron is equal to the mass of neutron because the mass of a neutron is kg and that of an electron is kg.