IIIIIIIVV Ch. 21 – Chemical Reactions II. Types of Chemical Reactions

A. Combustion CH 4 + 2O 2 CO 2 + 2H 2 O n the burning of a hydrocarbon in O 2 to produce carbon dioxide and water n Hydrocarbon = a substance made of only carbon and hydrogen C X H Y + O 2 CO 2 + H 2 O

B. Synthesis n the combination of 2 or more substances to form a compound n only one product A + B AB

B. Synthesis Example H 2 + Cl 2 2 HCl

C. Decomposition n a compound breaks down into 2 or more simpler substances n only one reactant AB A + B

C. Decomposition Example 2 H 2 O 2 H 2 + O 2

D. Single Replacement n one element replaces another in a compound metal replaces metal (+), or nonmetal replaces nonmetal (-) A + BC B + AC

D. Single Replacement Example Cu + 2AgNO 3 Cu(NO 3 ) 2 + 2Ag

AB + CD AD + CB E. Double Replacement n ions in two compounds change partners n cation of one compound combines with anion of the other

E. Double Replacement Example Pb(NO 3 ) 2 + K 2 CrO 4 PbCrO 4 + 2KNO 3