| Electrons | Protons | Neutrons |
| It is electrically negatively charged. | It is electrically positively charge. | It is electrically neutral. |
| Its mass is negligible. | Its mass is taken as one unit. | Its mass is also taken as one unit. |
| It is found revolving outside the nucleus. | It is present inside the nucleus. | It is also present inside the nucleus. |
| It represented as e. | It is represented as p. | It is presented as n. |
| It was discovered by J.J. Thomson. | It was discovered by Ernest Rutherford. | It was discovered by J. Chadwick. |