Do Now!

1. Do Now! • Balance this reaction: ______ HCl + ______ Cr  ______ CrCl2 + ______ H2

2. White Boards You will need 1 white board. You need to LISTEN to directions. Keep track of your score- it’s your participation grade for the day.

3. More Examples: Balance Chemical Equations- 2 min ____ K + ____ Cl2____ KCl

4. More Practice: Balance Chemical Equations ____ Pb + ____ H3PO4 ____ H2 + ____ Pb3(PO4)2

5. More Practice: Balance Chemical Equations ______ HCl + ______ Cr  ______ CrCl2 + ______ H2

6. Practice: Balance Chemical Equations ____ N2 + ____ H2 ____ NH3

7. More Examples: Balance Chemical Equations- 2 min ____ KClO3 ____ KCl + ____ O2

8. Types of Chemical Reactions

9. Objective 4-3 • SWBAT identify the five main types of chemical reactions.

10. Synthesis Reactions Two or more reactants combine to form a single new substance. A + B  AB Example: 2 Al + 3 Br2  2 AlBr3

11. Decomposition Reactions A single compound breaks down into two or more simpler products AB  A + B Example: 2 Al2O3  4 Al + 3 O2

12. Single Replacement Reactions One (lone) element replaces another element in a compound A + BC  AC + B Example: 2 K + 2 H2O  2KOH + H2

13. Double Replacement Reactions Cations are exchanged between compounds AB + CD  AD + CB Example: Ca(OH)2 + 2 HCl  CaCl2 + HOH

14. Combustion Reactions A hydrocarbon reacts with oxygen to produce carbon dioxide and water (and heat!) CxHx+ O2 CO2 + H2O or CxHxOx + O2 CO2 + H2O Example: 2 C2H6 + 7 O2  4 CO2 + 6 H2O

15. Examples – Identify Types of Reactions SO2+ Li2Se SSe2+ Li2O P2+ H2PH3

16. Practice – Identify Types of Reactions H3PO4 + KOH  K3PO4 + H2O C6H12 + O2  CO2 + H2O