1. : 1) Chemical bonds are the forces that hold atoms and ions together.

2. 2) Chemical structures or structural formulas are a graphical description of bond length and bond angle.

3. 3) Bonds can bend, stretch and rotate, and the chemical structure of a compound determines it properties.

4. 4) Atoms form bonds so that there is a stable electron configuration.

5. 5) Ionic bonds Form between oppositely charged ions Transfer of electrons

6. positive ions are called cations, negatively charged ions are called anions

7. Form networks of ions, NOT molecules When melted or dissolved in water ionic compounds conduct electricity

8. 6) Covalent bonds: One or more pairs of electrons are shared Usually occur between non-metal atoms Each line in a structural formula represents the sharing of one pair of electrons

9. 7) Metallic bonds: Electrons move freely between metal atoms Outermost energy levels overlap

10. 8) Polyatomic ions: Groups of covalently bonded atoms that have a charge so they act like an ion Denoted by parentheses in a formula Many polyatomic ions contain oxygen Amount of oxygen is used to determine the name – more oxygen uses “-ate”, less oxygen uses “-ite” example: NO 3 = nitrateNO 2 = nitrite

12. Determine if the following would have ionic or covalent bonds. Explain your reasoning. Magnesium Oxide MgO Strontium Chloride SrCl 2 Ozone O 2 Methanol CH 2 OH

13. Compound Names and Formulas: 1) Ionic compounds are named for their elements The cation is identified by the element name The anion is identified by an altered element name Example: NaCl = sodium chloride Ionic compounds have a charge of zero, so oxidation numbers must be balanced

14. Write formulas for the following ionic compounds: Lithium oxide Beryllium chloride Titanium (III) nitride

15. 2) Covalent compounds of two elements are named with numerical prefixes. Example dinitrogen tetroxide N 2 O 4

16. Organic and Biochemical Compounds 1) Organic compounds contain carbon and are covalently bonded. Carbon atoms form up to FOUR covalent bonds Compounds of just hydrogen and carbon are hydrocarbons

17. 2) A polymer is a molecule that is a long chain of similar molecules. Examples: rubber, wood, starch, protein and DNA Structure determines elasticity

18. 3) Biochemical compounds include carbohydrates, proteins, and DNA