The particles present in nucleus are called Nucleons.
Protons and neutrons are nucleons.
Comparison of properties ofconstituents of atom No Properties electron proton neutron 1. Symbol e p n 2. Relative charge -1 +1 0 3 Relative mass 0 1 1 4. Position Outside the nucleus In the nucleus In the nucleus 5. Discovered by J.J Thomson E. Goldstein James Chadwick
The maximum number of electrons that can be accommodated in any shell is given by 2n 2 formula where 'n' is the number of the shell.
The outermost shell of an atom cannot accommodate more than 8 electrons.
The shell closest to the nucleus has n=1 . Hence the maximum number of electrons in different shells are as follows; First orbit or K shell =2x1 2 = 2 Second orbit or L shell =2x 2 2 =8 Third orbit or M shell = 2x3 2 =18 and so on.