2.  When non-metals gain electrons to become ions, the name of the ion changes its ending to “ide”.  Fluorine fluoride  Chlorine chloride  Oxygen oxide

3.  Metals tend to have 1, 2 or 3 electrons in their outer orbit and tend to lose these electrons when they combine with other elements to form positive ions.

4.  Nonmetals tend to have 5, 6 or 7 electrons in their outer orbit. They all tend to gain electrons when they combine with metals to form compounds.

5.  As mentioned in a previous class sodium (Na) and chlorine (Cl) are highly reactive with each other and combine to produce a fairly stable compound called NaCl (salt).

6.  This compound is called an ionic compound because it made from positive and negative ions that transfer electrons from a metal to a non-metal.

7.  Positive and negative ions are attracted to each other due to their opposite charges.

8.  Sometimes in order to fill the valence shell some atoms have to combine with multiple atoms to become stable.

9.  A chemical formula is a way of expressing information about the atoms that make up a particular chemical compound.  The formula identifies each type of element by its chemical symbol and identifies the number of atoms of such element to be found in each molecule of that compound.  Ex. Methane is CH 4

10.  Magnesium chloride-MgCl 2  Aluminum fluoride-AlF 3  Glucose-C 6 H 12 O 6

11.  Ionic Compounds dissolve in water and form solutions that conduct electricity because they are made up of charged ions.  These ions separate from one another and are free to move around and carry an electrical current.

12.  Molecular Compounds are formed when nonmetals combine with other nonmetals.

13.  Review pages 188-189 and complete questions 1 and 2.

14.  EXAMPLE 1- What is the formula for the ionic compound formed by calcium and fluorine?  Step 1  Step 1 – Write the symbols of the elements with the metal first and non-metal second  Ca F  Step 2  Step 2 – Write the ion charge of each element  Ca +2 F -1

15.  Step 3  Step 3 – Determine how many of each you need to have an overall charge of zero.  Ca +2 F -1 F -1  Step 4  Step 4 - Write the formula using subscripts, after the element, to indicate how many you used.  Ca 1 F 2 CaF 2 ( 1 is not needed )

16.  What is the formula for the ionic compound formed by aluminum and sulfur?  Steps:  1) Al S  2) Al +3 S -2  3) Al +3 Al +3 S -2 S -2 S -2  4) Al 2 S 3

17.  Al +3 S -2  Al 2 S 3  Watch out for lowest terms:  Mg +2 O -2  Mg 2 O 2 = MgO - we can reduce to lowest terms

18.  When naming an ionic compound we simply write the name of the metal first and non- metal second. We change the ending of the non-metal name so that it ends in “ide.”

19.  1) NaCl – Sodium Chloride  2) CaBr 2 – Calcium Bromide  3) MgO – Magnesium Oxide

20.  Questions page 195 #1a, 3,4,5,6