Types of Reactions

Synthesis Atoms, molecules or compounds bond together to produce a larger compound. A + B  AB

Synthesis Na + Cl  NaCl Sodium + chlorine  sodium chloride HCl + NH 3  NH 4 Cl hydrochloric acid + ammonia  ammonium chloride

Decomposition Larger compounds break down into elements, molecules or compounds. AB  A + B

Decomposition CaBr 2  Ca + Br 2 Calcium bromide  calcium + bromine NH 4 NO 3  N 2 O + 2 H 2 O ammonium nitrate  nitrous oxide + water

Displacement Reactions Recall: Ionic compounds: metal + nonmetal In displacement reactions: - Metals can displace metals. - Nonmetals can displace nonmetals. * Hydrogen: because it’s a nonmetal with a “+” charge it can displace (and be displaced) by metals.

Single Displacement Only ONE element or polyatomic ion is displaced. AB + M  MB + A AB + N  AN + B A & M are metals B & N are nonmetals

Single Displacement 2AgNO 3 + Mg  Mg(NO 3 ) 2 + 2Ag ABAB MMBMBA CaI 2 + Br 2  CaBr 2 + I 2 ABABNANANB

Double Displacement TWO elements or polyatomic ions are displaced. AB + MN  AN + MB A & M are metals B & N are nonmetals

Double Displacement Pb(NO 3 ) 2 + 2KI  PbI 2 + 2KNO 3 ABAB MNANANMBMB CaCO 3 + HCl  H 2 CO 3 + CaCl 2 ABABMNMNANANMBMB

Double Displacement

Two things can occur: 1. Acid + base produces a salt and water. 2. A solid/precipitate forms in the solution.

Combustion A hydrocarbon reacts with oxygen.

Combustion Complete Combustion A large supply of oxygen is available. Hydrocarbon + oxygen  carbon dioxide + water (+ energy)

Combustion Incomplete Combustion Poor supply of oxygen. Hydrocarbon + oxygen  carbon dioxide + carbon monoxide + carbon + water (+ energy)

Terminology (g) for “gas” (l) for “liquid” (aq) for “aqueous” (water solution) (s) for “solid” or “precipitate” Pb(NO 3 ) 2 (aq) + 2KI (aq)  PbI 2 (s) + 2KNO 3 (aq)