Energy Levels

Energy Levels

1. Electrons are arranged in energy levels around the nucleus

   • Each successive energy level is further from the nucleus

2. 1st energy level=2 electrons

   • 2nd energy level=8 electrons
     • 3rd energy level=8 electrons

3. There is less energy in the shells the closer they are to the nucleus

   • The energy levels closet to the nucleus are filled first

4. Electron arrangement diagrams

   • These diagrams show only the arrangement of electrons in an atom

5. Electron configuration

   • This is a simpler way of representing the arrangement of electrons in an atom
     • Sodium(Na) can be written as 2:8:1
       • 2 is the first energy level, 8 is the second energy level and 1 is the third energy level