1. Chemistry 9.3 “Classifying Chemical Reactions”

2. I. Classifying Reactions A. Combination Reaction 1. Def – 2 or more substances combine to form a single substance 2. A + B  AB 3. Ex: 2 K + Cl 2  2 KCl 4. Demo – Magnesium + Oxygen -Why is this a combination reaction?

3. B. Decomposition Reaction 1. Def – a single compound is broken down into smaller products. 2. AB  A + B 3. Ex: Pg. 292 2 H 2 O  2 H 2 + O 2 4. Dynamite 2 C 7 H 5 N 3 O 6  7 CO + 3 N 2 + 5 H 2 O + 7 C

4. C. Single Replacement Reactions 1. Def – One element replaces another element in a compound. 2. A + BX  AX + B 3. Ex: 2 K + 2 H 2 O  2 KOH + H 2 4. Demo – I am going to add a small piece of magnesium to hydrochloric acid. The products produced is hydrogen gas and magnesium chloride. -Write the word equation -Balance the equation -Explain why this is a single replacement reaction

5. 4. Activity Series of Metals *For any replacement reaction, the replacing metal must be higher on the list than the one it is replacing *I will give you this* LithiumLi PotassiumK BariumBa StrontiumSr CalciumCa SodiumNa MagnesiumMg AluminumAl ManganeseMn ZincZn IronFe CadmiumCd CobaltCo NickelNi TinSn LeadPb HydrogenH CopperCu SilverAg MercuryHg GoldAu Decreasing Reactivity

6. 5. Ex: Will these reactions occur? Ag + LiOH Al + Pb(NO 3 ) 2 Li + CuCl 2 Na + H 2 O No Yes

7. D. Double Replacement Reactions 1. Def – involves an exchange of positive and negative ions between two reacting compounds. 2. AX + BY  AY + BX 3. Forms 3 possible compounds… -forms a precipitate (s) (AgNO 3 + NaCl) -forms a gas (g) (HCl + Mg) -forms a gas (g) (HCl + Mg) -forms water (l) (NaOH + HCl) *Pg. 295*

8. E. Combustion Reaction 1. Def – an element or compound that reacts with oxygen producing energy and light. 2. Ex: 2 Mg + O 2  2 MgO 3. Lighting a bunson burner… CH 4 + 2 O 2  CO 2 + 2 H 2 O

9. 4. Steel Wool Demo -Mass b/4 burning -Mass after burning -Why are they different? -Write the word equation -Write a balanced chemical equation -What type of reaction is this?