2. Catalyst – March 3 2 +7, 2010 1. Write the skeleton equation for: 1. Scandium and nitrogen gas combine to make scandium (II) nitride. 2. Calcium hydroxide and sodium nitrate react to form calcium nitrate and sodium hydroxide. 3. Hydrogen gas and oxygen gas produce water.

3. Today’s Agenda  Catalyst  Chemistry Prom 2010 Day 1!  Practice and Work Time  GEE Prep Time…What?  Exit Question

4. Today’s Objectives  SWBAT differentiate between synthesis and decomposition reactions.  SWBAT predict the products of synthesis and decomposition reactions.

5. Synthesis and Decomposition Reactions

6. On the request line…

7. Chemical Reactions  There are 5 types of chemical hook- ups (reactions) at the prom this year. 1. Combustion 2. Synthesis 3. Decomposition 4. Single Replacement 5. Double-replacement

8. Let’s come together Key Point #1: A SYNTHESIS REACTION is one in which two or more substances combine to form one new substance.  A + B  AB  Two substances are at the Chemistry Prom, dancing alone…they decide to hook up…

9. Let’s come together….  Synthesis reaction – two more substances combine to form one new substance  Two substances dancing alone decide to hook up… become a happy couple  A + B  AB Man I’m lonely Geez I could use a mate. Satisfaction

10. Practice  Show the synthesis of solid aluminum and oxygen gas.  What are the reactants? Al + O 2  What are the products? It’s a synthesis reaction, so we know Al and O are going to make a compound…. If the products aren’t in the question you need to KRISS KROSS to figure it out! Al (s) + O 2 (g)  AlOAl 3+ O 2- Al 2 O 3 DIATOMIC ALERT!

11. Practice 1. I broke my friend’s computer charger Write the chemical equation for the synthesis of rubidium nitride, Rb 3 N. 1. On your own: Write the chemical equation for the synthesis of strontium chloride.

12. Practice  Which reactions are SYNTHESIS reactions? A. C + O 2  CO 2 B. CaO + H 2 O  Ca(OH) 2 C. H 2 O  H 2 + O 2 D. 2Na + Cl 2  2NaCl E. Fe + CuSO 4  FeSO 4 + Cu F. 2K 3 PO 4 + 3H 2 SO 4  3K 2 SO 4 + 2H 3 PO 4 A, B, and D

13. I don’t think this is working out… Key Point #2: A DECOMPOSITION REACTION is one in which one substance breaks down into multiple substances, usually with the help of some kind of heat or energy  AB  A + B  A couple at the Chemistry Prom decides to break up

14. I don’t think this is working out…  Decomposition reaction – one substance breaks into multiple substances  A couple decides…well it is time to break up  AB  A + B I don’t think this is right for us… I want to see other people Satisfaction!

15. Practice  Show the decomposition water after electricity has passed through it.  What are the reactants? Water! H 2 O  What are the products? It’s a decomposition reaction, so we know the elements in water are going to break apart The question will specify if any compounds are formed H 2 O  H + O DIATOMIC ALERT! H 2 + O 2 Don’t forget to balance!

16. Practice 1. With Mr. J: Write the chemical equation for the decomposition of Na 2 S. 1. On your own: Write the chemical equation for the decomposition of VF 3.

17. More Practice!  Which reactions are DECOMPOSITION reactions? A. C + O 2  CO 2 B. CaO + H 2 O  Ca(OH) 2 C. H 2 O  H 2 + O 2 D. H 2 SO 4  H 2 + S + 2O 2 E. Fe + CuSO 4  FeSO 4 + Cu F. K 3 PO 4  K 3 P + 2O 2 C, D and F

18. GEE Prep

19. Exit Question 1. Identify the following reactions as synthesis or decomposition:  2 H 2 NO 3  2 H 2 + N 2 + 3 O 2  AB + C  ACB 2. Write the balanced chemical equation for the decomposition of solid magnesium oxide.