Unit 2-4: Rearrangement of Atoms in Chemical Reactions

Types of Chemical Reactions All chemical reactions follow the same basic formula: Reactants  Products

In grade 9 you learned that: If energy is required for a reaction to occur: Reactants + energy  Products - Then the reaction is classified as ENDOTHERMIC If energy is released or produced during a reaction: Reactants  Products + energy - Then the reaction is classified as EXOTHERMIC

Reactions can be further classified based on HOW the reactants combine and HOW the products form There are 6 common types of reactions that you need to be able to identify!

Classification of Chemical Reactions: The Soap-Opera of Chemistry

6 Main types of reactions Synthesis- “Love at first sight” Decomposition- “The big break-up” Single Replacement- “My best friends girlfriend” Double Replacement- “Revenge”  Also, Neutralization Combustion- “The player”

Synthesis- “Love at first sight” I like your braces I like your hat Hey Sally Can I get your number Hey Harry Basic equation: A+B AB

Synthesis- “Love at first sight” Two individual elements combine to produce a compound. Example: 2 Na + Cl2  2 NaCl

Practice: Mg + N2 

Practice: Al + F2 

Practice: K + O2 

Practice: Cd + I2 

Practice: Cs + P4 

Decomposition- “The Big Break-up” Whatever I was washing my hair Im leaving We are Through Where were you last night But, baby I love you I don’t believe you Basic Equation: AB A+B

Decomposition- “The Big Break-up” I am so over you The Breakdown of a compound into elements Example: 2 H2O  2 H2 + O2

Practice: AuCl3 

Practice: K2O 

Practice: MgF2 

Practice: Ca3N2 

Practice: CsI 

Single Replacement- “My Best Friends Girlfriend” Hey, Baby. How you doing? This Stinks! Hey Mark, here comes your friend Pierre Man, Marks Girl is pretty Hot! Oh Pierre! Mark Im leaving you Basic Eqn: AB + C  AC + B Or AB + C  CB + A

Single Replacement- “My Best Friends Girlfriend” “Free” element must be the more reactive element for a reaction to occur ( Pierre is more suave then Mark) Basically, a compound and element react to produce a different compound and element Example: 2K + 2HCl  2KCl + H2

Practice: PbCl4 + Al 

Practice: Na + Cu2O 

Practice: CuF2 + Mg 

Practice: Cl2 + CsBr 

Practice: Be + Fe(NO3)2 

Double Replacement- “Revenge” I have to get Pierre back. Hey Chloe do you want to go out I can’t believe Chloe would do that Ok Pierre, Im sick of you Chloe was my one true love, but Marks girl is looking pretty Hot. Basic Eqn: AB + CD  AD +BC

Double Replacement- “Revenge” Two compounds react to produce two different compounds. Ex: 2 KI(aq) + Pb(NO3)2(aq)  PbI2(s) + 2 KNO3(aq)

Practice: CaS + NaOH 

Practice: K3PO4 + MgI2 

Practice: SrCl2 + Pb(NO3)2 

Practice: AlCl3 + CuNO3 

Practice: AgNO3 + Na2CrO4 

ACID + BASE  SALT + WATER Psst…. Neutralization Reactions are a specific type of Double Replacement Reaction!! ACID + BASE  SALT + WATER H2SO4 + Ca(OH)2 → CaSO4 + 2H2O Acid Base Salt Water

Practice: HBr + NaOH 

Practice: H3PO4 + Mg(OH)2 

Practice: HCl + Pb(OH)2 

Practice: Al(OH)3 + HClO4 

Combustion- “The player” That was a great date Baby, I love you Ashley you’re my BFF Hey Ladies (3 weeks later) Basic Eqn: CxHy + O2  CO2 + H2O

Combustion- “The player” Honey, Why is Ashley’s number on your phone? A hydrocarbon reacts with oxygen to produce carbon dioxide,water and energy (very exothermic!)

Practice: C3H8 + O2 

Practice: C4H10 + O2 

Practice: C2H4 + O2 

Practice: C6H12O6 + O2 

Practice: C12H22O11 + O2 

Practice! Identify each of the following as one of the 6 major types of reactions: PbO2 → Pb + O2

Practice! Mg + AgNO3 → Mg(NO3)2 + Ag Identify each of the following as one of the 6 major types of reactions: Mg + AgNO3 → Mg(NO3)2 + Ag

Practice! Identify each of the following as one of the 6 major types of reactions: H2 + Cl2 → 2HCl

Practice! Identify each of the following as one of the 6 major types of reactions: 2NaI + F2 → 2NaF + I2

Practice! Identify each of the following as one of the 6 major types of reactions: C12H22O11 + 12O2 → 12CO2 + 11H2O

Practice! Identify each of the following as one of the 6 major types of reactions: 2HI → H2 + I2

Practice! 2LiCl + Br2 → 2LiBr + Cl2 Identify each of the following as one of the 6 major types of reactions: 2LiCl + Br2 → 2LiBr + Cl2

Practice! H2SO4 + 2NaOH → Na2SO4 + 2H2O Identify each of the following as one of the 6 major types of reactions: H2SO4 + 2NaOH → Na2SO4 + 2H2O

Practice! Silver + chlorine → silver chloride Identify each of the following as one of the 6 major types of reactions: Silver + chlorine → silver chloride

Practice! Sulfur dioxide → sulfur + oxygen Identify each of the following as one of the 6 major types of reactions: Sulfur dioxide → sulfur + oxygen

Practice Problems Page 265 Check Your Understanding Page 271 #1-6

Answers to CYU pg.271 a) Neutralization b) Synthesis c) Double replacement d) Synthesis e) Combustion f) Double replacement g) Single replacement (metal) h) Neutralization i) Decomposition j) Single replacement (metal)

Answers to CYU pg.271 2. Combustion reactions will always have O2 as one of the reactants. 3. 1a of these questions is both a neutralization and a double replacement reaction. 4. a) Synthesis: 4Na + O2  2Na2O b) Double Replacement: Na2SO4 + CaCl2  2NaCl + CaSO4

Answers to CYU pg.271 4. c) Combustion: C3H8 + 5O2  3CO2 + 4H2O d) Neutralization: H2SO4 + 2KOH  K2SO4 + 2H2O e) Decomposition: 2AlCl3  2Al + 3Cl2 f) Single Replacement: 3Cd + 2Au(NO3)3  3Cd(NO3)2 + 2Au

Answers to CYU pg.271 4. g) Double replacement: Sr(OH)2 + PbBr2  SrBr2 + Pb(OH)2 h) Combustion: C6H12O6 + 6O2  6CO2 + 6H2O i) Synthesis: 2N2 + 3O2  2N2O3 j) Single replacement: 2HNO3 + Zn  Zn(NO3)2 + H2

Answers to CYU pg.271 5. a) Synthesis: 6Na + N2  2Na3N b) Decomposition: 2AlF3  2Al + 3F2 c) Single Replacement: 3CuSO4 + 2Al  Al2(SO4)3 + 3Cu d) Double Replacement: CaI2 + Pb(NO3)2  Ca(NO3)2 + PbI2

Answers to CYU pg.271 5. e) Combustion: 2C4H10 + 13O2  8CO2 + 10H2O f) Double replacement: AgNO3 + NaBr  AgBr + NaNO3 g) Single replacement (non-metal): 2CsI + Cl2  2CsCl + I2 h) Neutralization: HCl + NaOH  NaCl + H2O

Answers to CYU pg.271 5. i) Double replacement: K2Cr2O7 + 2AgNO3  Ag2Cr2O7 + 2KNO3 j) Combustion: C5H10O5 + 5O2  5CO2 + 5H2O 6. 2Fe + 3Cl2  2FeCl3