Temas De Cultura

Luis Diego Rodríguez De Jesús
Mr. Hernández
Sciences 10 Grade
November, 28, 2012
Lewis Dot Diagram
Lewis structures (also known as Lewis dot diagrams, electron dot diagrams, and electron
dotstructures) are diagrams that show the bonding between atoms of a molecule and the
lone pairs of electrons that may exist in the molecule.
The Lewis structure was named after Gilbert Newton Lewis,who introduced it in his
1916 article The Atom and the Molecule. Lewis structures show each atom and its position
in the structure of the molecule using its chemical symbol. Lines are drawn betweenatoms
that are bonded to one another (pairs of dots can be used instead of lines). Excess electrons
that form lone pairs are represented as pairs of dots, and are placed next to the atoms.
The totalnumber of electrons represented in a Lewis structure is equal to the sum of the
numbers of valence electrons on each individual atom. Non-valence electrons are not
represented in Lewis structures.Drawing Lewis Dot Structures
1. Add up the total number of valence electrons in the molecule by totaling the valence
electrons on each atom in the molecule or polyatomic ion.
* If youare drawing a Lewis Structure for a polyatomic ion:
1. Negative Ion:  Add the number of electrons equal to the negative charge on the ion.
2. Positive Ion:  Subtract the number ofelectrons equal to the positive charge on the ion.
2. Draw the skeleton structure of the molecule or polyatomic ion in which the covalent bonds between the atoms are drawn as single lines.  Eachbond equals two valence electrons.  If the molecule has more than two atoms, the atom with the lowest electronegativity is generally the central atom and is written in the middle.
3. Distributevalence electrons around the outer atoms as nonbonding electrons to until each atom has a complete outer shell (i.e. 8 electrons except for H which has only 2 valence electrons).
4. Add the...