Structure of the atom
Everything in the world is made up of atoms. The structure of the atom is what gives an element its chemical and physical properties.
Atoms are made up of three smaller particles called Subatomic particle, with a negative charge and a negligible mass relative to protons and neutrons., protons and neutrons.
Electrons
Negatively charged particles that spin around the positive centre of the atom in circles called energy levels. Their mass is so small it is nearly zero.
Protons
Positively charged particles that are contained in the nucleus of the atom (the centre) they have a mass of 1amu (atomic mass unit).
Neutrons
Particles with no charge are also contained in the The central part of an atom. It contains protons and neutrons, and has most of the mass of the atom. The plural of nucleus is nuclei. of the atom. They too have a mass of 1amu.
The nucleus has an overall positive charge as it contains the protons.
| Particle | Mass | Charge | Location |
| Electron | Approx 0 | -1 | Energy level |
| Proton | 1 amu | +1 | Nucleus |
| Neutron | 1 amu | 0 | Nucleus |
| Particle |
| Mass |
| Charge |
| Location |
| Electron |
| Approx 0 |
| -1 |
| Energy level |
| Proton |
| 1 amu |
| +1 |
| Nucleus |
| Neutron |
| 1 amu |
| 0 |
| Nucleus |
Every atom has no overall charge (neutral). This is because they contain equal numbers of positive protons and negative electrons. These opposite charges cancel each other out making the atom neutral.