ELECTRONIC STRUCTURE: DRAWING ELECTRON DOT DIAGRAMS: November 1st, 2010

Drawing electron dot diagrams:

• The nucleus is represented by the atomic symbol
• For individual elements determine the number of valence electrons (electrons in the outermost energy level of an atom; for most atoms, it is available to be gained, lost, or shared in the formation of chemical bonds)
• 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 to make a lone pair (a pair of electrons- 2 of them)

An atom of Neon can be represented by the diagram on the left. But in this case, we are drawing electronic dot diagrams. For neon, we must determine a) number of valence electrions b) place dots around the element to represent the valence electrons. Since there are 10 electrons, 2 go in the first shell but the rest (8 electrons) are in the second shell, therefore, these electrons are considered to be in the valence shell, and we label them.

Lewis Diagrams for compounds and Ions:

-In covalent compounds electrons are shared

1. Determine the number of valence electrons for each atom in the molecule

2. Place atoms so that valence electrons are shared to fill each orbital.

Compound:

We have just learned how to draw a Lewis dot diagram for a single element and a compound. An Ionic Compound presented as an electronic dot diagram has the follow:

-An ionic compounds electrons transfer from one element to another

-Determine the number of valence electrons on the cation (+) and move these to the anion (-).

-Draw [ ] around the metal and non-metal (write the charges on the outside bracket)



An example of an ionic compound: Lewis Dot Diagram



 Next we have a more complicated diagram, because it consists of a "DOUBLE BOND".

DOUBLE & TRIPLE BONDS:

Sometimes the only way covalent compounds can fill all their valence levels is if they share more than one electron.

This periodic table can also help you when drawing Electronic Dot Diagrams. Notice a trend in each group (group 1 has 1 valence electron, group 15 has 5 valence electrons and so on)

Yay, you've mastered the art of drawing Electronic dot Diagrams!

Post by Ren Flores