types of chemical reactions€¦ · §double displacement §decomposition §synthesis §combustion....
TRANSCRIPT
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
SINGLE DISPLACEMENT
§ (aka single replacement)§ One element displaces another element in a compound
§Based on activity series of reactivity §Metal replaces metal (+)§Nonmetal replaces nonmetal (-)
§ General form: § element + compound à element + compound
A + BC ® B + AC
General Types of Single Displacement Reactions:
§Replacement of metal by more active metal§Ex: Al + Fe(NO3)2 à Fe + Al(NO3)3
§Replacement of H in water by a more reactive Group 1 metal§Ex: Na + H2O à NaOH + H2
§Replacement of H in water by more reactive Group 2 or transition metal§Ex: Mg + H2O à MgO + H2
§Replacement of H in an acid by a more reactive metal§Ex: Mg + HCl à MgCl2 + H2
§Replacement of a halogen (nonmetal) by a more reactive halogen§Ex: Cl2 + NaBr à NaCl + Br2
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 à compound + compound
AB + CD ® AD + CB
General types of double displacement reactions:
§Formation of water (acid/base neutralization)§Ex: H2SO4 + NaOH à Na2SO4 + H2O
§Formation of a gas§Ex: CaCO3 + HCl à CaCl2 + H2O + CO2
§Formation of a precipitate (insoluble substance)§Ex: Pb(NO3)2 + NaI à PbI2 + NaNO3
DECOMPOSITION
§A compound breaks down into 2 or more simpler substances§Only one reactant§General form:
§compound à two or more substances
AB ® A + Bone reactant
General types of decomposition reactions:
§Decomposition of binary compounds§Ex: NaCl à Na + Cl2
§Decomposition of metal carbonates to form metal oxides and CO2§Ex: CaCO3 à CaO + CO2
§Decomposition of metal hydroxides to form metal oxides and H2O§Ex: Mg(OH)2 à MgO + H2O
§Decomposition of metal chlorates to form metal chlorides and O2§Ex: KClO3 à KCl + O2
SYNTHESIS
§The combination of 2 or more substances to form a compound§Only one product§General form:
§element or compound + element or compound à compound
A + B ® ABone product
General types of synthesis reactions:
§Oxygen reacts with metals to form metal oxides§Ex: O2 + Mg à MgO
§Two nonmetals react to form a covalent bond§Ex: S + O2 à SO2
§Metals react with nonmetals to form ionic “salts”§Ex: Mg + Cl2 à MgCl2
COMBUSTION
§Contains oxygen (O2)§Usually contains hydrocarbons (H and C molecules) combine with oxygen
to produce a large amount of energy, which produce CO2 + H2O§General form:
§Hydrocarbon + oxygen à carbon dioxide + water
§Ex: The burning of propaneC3H8 + 5O2 à 3CO2 + 4H2O
CxHy + O2 ® CO2 + H2Ohydrocarbon
YOU TRY!
Balance and classify the following chemical reactions:1. __ Na3PO4 + __ KOH à ___ NaOH + __ K3PO4
2. __ P4 + __ O2 à __ P2O3
3. __ NO2 à __ O2 + __ N2
4. __ AgNO3 + __ Cu à __ Cu(NO3)2 + __ Ag
5. __ C3H6O + __ O2 à __ CO2 + __ H2O
1 3 3 1
double displacement1 3 2
synthesis2 2 1
decomposition2 1 1 2
single displacement1 4 3 3
combustion