Types of Chemical Reactions SynthesisSynthesis (Combination) reaction DecompositionDecomposition reaction Single-replacementSingle-replacement reaction Double-replacement reaction Combustion reaction (of a hydrocarbon) A + B  AB AB  A + B A + BC  AC + B AB + CD  AD + CB CH + O 2  CO 2 + H 2 O use activity series to predictactivity series elementcompoundelementcompound

Chemical Equations

Synthesis Reaction Direct combination reaction (Synthesis) General form: A + B  AB element orelement or compoundcompound Na Cl Na Cl 2 Na + Cl 2  2 NaCl  Cl Na Cl

Synthesis Reaction Direct combination reaction (Synthesis) General form: A + B  AB element orelement or compoundcompound Na + Cl - Na ClNa Cl Na + Cl - 2 Na + Cl 2  2 NaCl

Synthesis Reactions CO 2 + H 2 O C 6 H 12 O 6 + O 2 H 2 + O 2 H 2 O Na + Cl 2 NaCl 66 6 Photosynthesis Formation of water Formation of salt A + B AB General Form

H H H H Decomposition Reaction H H H H O Decomposition reaction 2 H 2 O 2 H 2 O2O2 General form: ABAB compoundtwo or more elements or compounds OO O

H 2 O H 2 + O 2 electricity Decomposition Reactions H 2 O 2 H 2 O + O 2 NI 3 N 2 + I Hydrogen Peroxide Electrolysis of water 22 Nitrogen triiodide AB A + B General Form 2 3

Single and Double Replacement Reactions Double-replacement reaction CaCO HCl  CaCl 2 + H 2 CO 3 General form: AB + CD  AD + CB Single-replacement reaction Mg + CuSO 4  MgSO 4 + Cu General form: A + BC  AC + B

Ca Activity Series Foiled again – Aluminum loses to Calcium Element Reactivity Li Rb K Ba Ca Na Mg Al Mn Zn Cr Fe Ni Sn Pb H 2 Cu Hg Ag Pt Au Halogen Reactivity F 2 Cl 2 Br 2 I 2 Printable Version of Activity Series Printable Version of Activity Series

Single-Replacement Reactions FeCl 2 + Cu MgBr 2 + Cl 2 “Magic blue-earth” Zinc in Sodium nitrate A + BC AC + B General Form NR Can Fe replace Cu? Yes Li Rb K Ba Ca Na Mg Al Mn Zn Cr Fe Ni Sn Pb H 2 Cu Hg Ag Pt Au F 2 Cl 2 Br 2 I 2 Can Zn replace Na? No Can Br replace Cl? Kinda Fe + CuCl 2 Zn + NaNO 3 MgCl 2 + Br 2 Activity Series

Mg + AlCl 3 Al + MgCl 2 Predict if these reactions will occur Al + MgCl 2 Can magnesium replace aluminum? Activity Series YES, magnesium is more reactive than aluminum Can aluminum replace magnesium? Activity Series NO, aluminum is less reactive than magnesium. Therefore, no reaction will occur. No reaction MgCl 2 + Al No reaction The question we must ask is can the single element replace its counterpart? metal replaces metal or nonmetal replaces nonmetal. Order of reactants DOES NOT determine how they react.

Double Replacement Reaction K 2 CO 3 (aq) Potassium carbonate BaCl 2 (aq) Barium chloride 2 KCl (aq) Potassium chloride BaCO 3 (s) Barium carbonate ++

Formation of a solid: AgCl AgNO 3 (aq) + KCl(aq)  KNO 3 (aq) + AgCl(s)

Copyright © 2007 Pearson Benjamin Cummings. All rights reserved. PbI 2 K 1+ Pb 2+ lead (II) chloride + potassium iodide Cl 2 I Pb 2+ Pb K 1+ K Cl 1- I 1- Cl 1- I 1- KCl potassium chloride lead (II) iodide + (aq) (ppt) + +

Copyright © 2007 Pearson Benjamin Cummings. All rights reserved. PbI 2 K 1+ Pb 2+ lead (II) chloride + potassium iodide Cl 2 I Pb 2+ Pb K 1+ K Cl 1- I 1- Cl 1- I 1- KCl potassium chloride lead (II) iodide + (aq) (ppt) + +

Solubility Rules 1. Most nitrates are soluble. 2.Most salts containing Group I ion and ammonium ion, NH 4 +, are soluble. 3.Most chloride, bromide, and iodide salts are soluble, except Ag +, Pb 2+ and Hg Ohn-Sabatello, Morlan, Knoespel, Fast Track to a 5 Preparing for the AP Chemistry Examination 2006, page Most sulfate salts are soluble, except BaSO 4, PbSO 4, Hg 2 SO 4, and CaSO 4. 5.Most hydroxides except Group 1 and Ba(OH) 2, Sr(OH) 2, and Ca(OH) 2 are only slightly soluble. 6.Most sulfides, carbonates, chromates, and phosphates are only slightly soluble.

Combustion Reactions A substance combines with oxygen and produces a combination of water and carbon dioxide. Usually involves hydrocarbons C x H y + O 2  CO 2 + H 2 O C 3 H 8 + 5O 2  3CO 2 + 4H 2 O

Write a balanced chemical equation for the following combustion reactions: A. C 5 H 12 B. C 22 H 46 C. C 15 H 28 + O 2  CO 2 + H 2 O O 2  CO 2 + H 2 O