ELECTRON CONFIGURATION Bohr Model & Lewis Dot Structures

How are electrons arranged? Electrons are pulled in by the positive attraction of the protons. Their own energy keeps them in orbit around the nucleus. Electrons will orbit the nucleus at specific distances called energy levels.

K L M N O P Energy Level Names Energy levels are assigned letters to identify each level. They are: K L M N O P

Order of energy levels The electrons will always fill the energy level closest to the nucleus first.

Can only hold 2 electrons K energy level Closest to the nucleus. Can only hold 2 electrons

Bohr Model Electrons in the K energy level are always drawn on opposite sides because the electrons repel each other.

Can hold 8 electrons L Energy Level Has more space, but electrons will still push each other away

Electrons in the L energy level should always be far apart. Bohr Model Electrons in the L energy level should always be far apart.

When an atom has 8 electrons in its outer level it is called an octet. For energy levels that are larger than K, 8 electrons fill the entire area and repel other electrons into the next level.

8 electrons in the outer level is VERY stable. OCTET 8 electrons in the outer level is VERY stable. Atoms want to have 8 electrons in their outer level.

Electrons in the Outermost Level These electrons are the most important. They are the electrons that can interact with other atoms. These electrons are called VALENCE electrons.

Writing the Electron Configuration List the energy levels from innermost to outermost. When listed as a column move from bottom to top.

Writing the Electron Configuration Oxygen ______ M VALENCE L ELECTRONS: K 6 ______ 6 2 ______

Magnesium

Lewis Dot Structures Lewis Dot Structures only draw the valence electrons. When drawing, put the symbol name in the middle surrounded by electrons Start at the top and work around clockwise O