Electron Arrangements in Atoms

Energy Levels 

• Electrons in different shells have different amounts of energy, these are called main energy levels and are labelled 1, 2 and 3, etc.
• Energy levels are divided into sub-levels called s, p, d and f
• Electron's cloud of negative charge fills a volume in space called its atomic orbital
• Different sub-levels have different shapes too
• First energy level has a single s-orbital,  the second has a single s-orbital and three p-orbitals, the third has a single s-orbital, three p-orbitals and five d-orbitals, and so on
• Any single atomic orbital can…