Electron structure (Electron dot diagrams)

In today class we learned how the electrons are present in each element in either basic element form or as an ion. In an ion the element is either positively or negatively charged and either lose or gain an electron depending on the charge of the element. A negatively charged ion would gain electrons and a positively charged ion would lose electrons.

Drawing Electron Dot diagrams:
• To represent the nucleus, write the atomic symbol
• For individual elements determine the number of valence electrons
• Electrons are represented by dots around the symbol
• Four orbitals (one of each side of the nucleus) each holding a max of 2 electrons
*Each orbital gets 1 electron before they pair up
e.g.

Lewis diagrams for Compounds and Ions:
• In covalent compound, electrons are shared
1. Determine the number of valence electron for each atom in the molecule
2. Place atoms so that valence electrons are shared to fill each orbital
e.g.

Ionic Compounds:
• In ionic compounds electrons transfer from one element to another
• Determine the number of valences on the cation is more than to the anion
• Draw [] around the metal & non metals
• Write the charges outside the brackets
e.g.