1 / 11

8-2: Types of Chemical Reactions

8-2: Types of Chemical Reactions. Classifying Chemical Changes. The products of a chemical reaction may often be predicted by applying known facts about common reaction types Five general types of reactions : Single displacement Double displacement Decomposition Synthesis Combustion.

idana
Download Presentation

8-2: Types of Chemical Reactions

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. 8-2: Types of Chemical Reactions

  2. Classifying Chemical Changes • The products of a chemical reaction may often be predicted by applying known facts about common reaction types • Five general types of reactions: • Single displacement • Double displacement • Decomposition • Synthesis • Combustion

  3. Single Displacement • (aka single replacement) • One element displaces another element in a compound • Metal replaces metal (+) • Nonmetal replaces nonmetal (-) • General form: • element + compound  element + compound A + BC  B + AC

  4. General types of single displacement reactions: • An active metal will replace the metallic ion in a compound of a less active metal. • Ex: Fe + Cu(NO3)2  Fe(NO3)2+ Cu • Some active metals such as sodium and calcium will react with water to give a metallic hydroxide and hydrogen gas. • Ex: Ca + 2H2O  Ca(OH)2+ H2 • Active metals such as zinc, iron, and aluminum will displace the hydrogen in acids to give a salt and hydrogen gas. • Ex: Zn + 2HCl  ZnCl2+ H2 • An active nonmetal will displace a less active nonmetal. • Ex: Cl2+ 2NaBr  2NaCl + Br2

  5. Double Displacement • (aka double replacement) • Ions in two compounds “change partners” • Cation of one compound combines with the anion of the other compound • General form: • compound + compound  compound + compound AB + CD  AD + CB

  6. General types of double displacement reactions: • A reaction between an acid and a base yields a salt and water. Such a reaction is a neutralization reaction. • Ex: 2KOH+ H2SO4 K2SO4+ 2H2O • Reaction of a salt with an acid forms a salt of the acid and a second acid that is volatile. • Ex: 2KNO3+ H2SO4 K2SO4 + 3HNO4 • Reactions of some soluble salts produce an insoluble salt and a soluble salt. • Ex: AgNO3+ NaCl  AgCl+ NaNO3

  7. Decomposition • A compound breaks down into 2 or more simpler substances • Only one reactant • General form: • compound  two or more substances AB  A + B

  8. General types of decomposition reactions: • When some acids are heated, they decompose to form water and an acidic oxide. • Ex: H2CO3 CO2+ H2O • When some metallic hydroxides are heated, they decompose to form metallic oxide and water. • Ex: Ca(OH)2 CaO+ H2O • When some metallic carbonates are heated, they decompose to form a metallic oxide and carbon dioxide. • Ex: Li2CO3 Li2O + CO2 • Most metallic oxides are stable, but a few decompose when heated. • Ex: 2HgO  2Hg + O2 • Some compounds cannot be decomposed by heat, but can be decomposed into their elements by electricity. • Ex: 2NaCl  2Na+ Cl2

  9. Synthesis • The combination of 2 or more substances to form a compound • Only one product • General form: • element or compound + element or compound  compound A + B  AB

  10. General types of synthesis reactions: • Two or more elements combine to form a compound. • Ex: Fe + S  FeS • An acid anhydride, nonmetallic oxide, combines with water to give an acid. • Ex: SO2+ H2O  H2SO3 • A basic anhydride, metallic oxide, combines with water to form a base. • Ex: Na2O + H2O  2NaOH • A basic oxide combines with a nonmetallic oxide to form a salt. • Ex: CO2+ Na2O  Na2CO3

  11. Combustion • Contains oxygen • Hydrocarbons form CO2 + H2O • Ex: The combustion of hydrogen2H2+ O2 2H2O • Ex: The burning of propaneC3H8+ 5O2 3CO2+ 4H2O

More Related