Recognizing Types of Chemical Reactions How can one identify the type of chemical reaction from an equation?

Synthesis (Combination) Two or more reactants combine to form one product A + B  AB Examples: 2 H2 + O2  2 H2O 4 Fe + 3 O2  2 Fe2O3 CO2 + H2O  H2CO3

Decomposition One reactant breaks apart into two or more products AB  A + B Examples: 2 HI  H2 + I2 CaCO3  CaO + CO2

Single Replacement Two reactants and two products (look for elements) element + compound  element + compound A + BC  B + AC Examples: Cu + 2 AgNO3  Cu(NO3)2 + 2 Ag Cl2 + 2 NaBr  2 NaCl + Br2

Double Replacement Two reactants and two products (all are compounds) Two compounds switch positive and negative ions AB + CD  AD + CB Examples: AgNO3 + NaCl  AgCl + NaNO3 Na2S + 2 HCl  H2S + 2 NaCl

Organic Combustion Two reactants and two products (C,H + O2  CO2 + H2O) Examples: CH4 + 2 O2  CO2 + 2 H2O 2 C2H6 + 7 O2  4 CO2 + 6 H2O