Question

In atom why proton and neutron composed together why not proton and alectron and why not electron and neutron ?

Answer 1

as nucleus is a heavy part in an atom which has to be strong and powerful for attracting other atoms and particles and it should be positive charge as it is the most important part of an atom.

Answer 2

The number of electrons in a neutral atom is equal to the number of protons. The mass number of the atom (M) is equal to the sum of the number of protons and neutrons in the nucleus. The number of neutrons is equal to the difference between the mass number of the atom (M) and the atomic number (Z).