5 TYPES OF REACTIONS Combination (Synthesis) Decomposition Single replacement Double replacement Combustion

COMBINATION (SYNTHESIS) Two or more substances react to form a single substance. Reactants are usually two elements or two compounds. S(s) + O2(g) → SO3(g) 2 3 2

COMBINATION (SYNTHESIS) Two or more substances react to form a single substance. Reactants are usually two elements or two compounds. Mg(s) + O2(g) → MgO(s) 2 2

DECOMPOSITION A single compound is broken down into two or more products. calcium carbonate → calcium oxide + carbon dioxide CaCO3(s) → CaO(s) + CO2(g)

DECOMPOSITION A single compound is broken down into two or more products. hydrogen peroxide → water + oxygen H2O2(aq) → H2O(g) + O2(g) MnO2 2 2

SINGLE REPLACEMENT Atoms of an element replace the atoms of a second element in a compound. metal replaces metal nonmetal replaces nonmetal

SINGLE REPLACEMENT must use activity series: metal above will replace Li K Ca Na Mg Al Zn Fe Pb H* Cu Hg Ag SINGLE REPLACEMENT must use activity series: metal above will replace a metal ion below higher metals lose electrons the easiest

SINGLE REPLACEMENT Cu(s) + AgNO3(aq) → Ag(s) + CuNO3(aq) Ag(s) + NO R E ACTION!

SINGLE REPLACEMENT Zn(s) + Fe(OH)2(aq) → Fe(s) + Zn(OH)2(aq) Na(s) + K2SO3 (aq) → NO R E ACTION!

MORE SINGLE REPLACEMENT nonmetal can replace a nonmetal applies to halogens activity of halogens DECREASES as you go down group 7A F can replace all others Cl can replace Br, I, etc.

SINGLE REPLACEMENT chlorine gas is bubbled through a soln of potassium bromide: Cl2(g) + KBr(aq) → Br2(l) + KCl bromine liquid is added to a soln of sodium chloride: Br2(l) + NaCl(aq) → no reaction! 2 2

1) C + 2 H2 → CH4 2) 4 B + 3 O2 → 2 B2O3 3) 2 SO2 + O2 → 2 SO3 5) B2H6 + 3 O2 → B2O3 + 3 H2O 6) 2 CH3OH + 3 O2 → 2 CO2 + 4 H2O 7) C2H5OH + 3 O2 → 2 CO2 + 3 H2O 8) 2 NiS + 3 O2 → 2 SO2 + 2 NiO

9a) Hg + Ca(NO3)2 → no rxn b) Al + 3 AgNO3 → 3 Ag(s) + Al(NO3)3 c) Zn + 2 HCl → H2(g) + ZnCl2 d) 2 H2O + 2 Li → H2(g) + 2 LiOH e) Pb + MgSO4 → no rxn f) 2Fe(NO3)3+3 Mg → 2 Fe(s) + 3Mg(NO3)2 g) Al + H2O → no rxn h) 2 Al + 3 H2SO3 → 3 H2(g) + Al2(SO3)3