1. B.6 Symbols, Formulas, and Equations

2. Chemical Language Letters Symbols Words Formulas Sentences Equations

3. Chemical Symbols  The language of chemistry  Worldwide  First letter is capitalized, second is lowercase  Examples page 34

4. Periodic Table of the Elements  A chemists best friend  Organizes the elements according to number of protons  Creates families of elements with similar properties

5. Chemical Formulas  Represents a substance  Shows the elements present  Indicates the number of each element present using subscripts  Example: H2OH2O 2 Hydrogen atoms 1 Oxygen atom

6.  Propane is made of 3 carbon atoms and 8 hydrogen atoms C3H8C3H8 Is this a compound or a molecule? How do you know?

7. Chemical Reactions  The breaking and forming of chemical bonds  Represented by: chemical equations 2 H 2 + O 2  2 H 2 O

8. Parts of the equation:  Reactants - substances that are changing  Written to the left of an arrow  Products - substances formed with new chemical properties…  Written to the right of the arrow

9. Equations  Are always balanced  Use atom counting to determine  Referred to as an “atom inventory”

10. 2 H 2 + O 2  2 H 2 O  2 hydrogen molecules react with 1 oxygen molecule to yield 2 molecules of water  Atom count: reactants: 4 atoms of hydrogen 2 atoms of oxygen products:4 atoms of hydrogen 2 atoms of oxygen

11. Did you notice…  The reactants hydrogen and oxygen both have the subscript “2”  These two elements are diatomic  They exist as two bonded atoms of the same element ALWAYS  YOU MUST MEMORIZE THESE 7 ELEMENTS!!!!

12. Diatomic gases