Lewis Structure

Lewis Structure

1. A 2-dimensional model

   • Straight Lines=covalent bonds
   • unbonded valence electrons=dots

2. Bonding Pairs=bonds are formed by pairs of valence electrons in a space between two atoms

3. Lone Pairs: Pairs of electrons that are attracted to only on atom

4. Atoms are most stable when their outer most electron shells are filled.

   • Exceptions: Hydrogen can only hold two electrons. Elements in the third row of the periodic table and below often have more than eight valence electrons

5. Sidenotes

   • Model: anything that represents something else physical or conceptual
   • The only thing connecting two atoms together in a chemical bond is a bunch of electrons-> they are in constant motion
   • 1916 Gilbert Newton Lewis Described covalent bonds as 2 atoms sharing electrons

6. Process

   • 1. Figure out how many valence electrons are in each atom. Hydrogen has 1 valence electron. Oxygen has 6 valence electrons.
     • 2. Multiply the number of valence electrons by the number of atoms. H=1 valence electron per atom x 2 atoms = 2 electrons. O= 6 valence electrons x 1 atom = 6 electrons
       • 3. Layout the molecules and create the bond
         • Types of Bonds
           • Double Bond: Bond in which two pairs of electrons are shared by a pair of atoms (=)
           • Triple Bond: bond in which three pairs of electrons are shared by a pair of atoms
   • H20