IIIIIIIVV Ch. 8 – Chemical Reactions III. Types of Chemical Reactions (p )

A. Combustion CH 4 (g) + 2O 2 (g) CO 2 (g) + 2H 2 O(g) n the burning of any substance in O 2 to produce heat A + O 2 B

Na(s)+ O 2 (g) C 3 H 8 (g)+ O 2 (g) A. Combustion n Products: contain oxygen hydrocarbons form CO 2 + H 2 O CO 2 (g)+ H 2 O(g) Na 2 O(s) 4 2

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

B. Synthesis H 2 (g) + Cl 2 (g) 2 HCl(g)

Al(s)+ Cl 2 (g) AlCl 3 (s) B. Synthesis n Products: ionic - cancel charges covalent - hard to tell

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

C. Decomposition 2 H 2 O(l) 2 H 2 (g) + O 2 (g)

KBr(l) K(s) + Br 2 (l) 2 2 C. Decomposition n Products: binary - break into elements others - hard to tell

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

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

Single Replacement free element must be more active (check activity series)

Fe(s)+ CuSO 4 (aq) Cu(s)+ FeSO 4 (aq) D. Single Replacement n Products: metal metal (+) nonmetal nonmetal (-) free element must be more active (check activity series) Br 2 (l)+ NaCl(aq) N.R.

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 Pb(NO 3 ) 2 (aq) + K 2 CrO 4 (aq) PbCrO 4 (s) + 2KNO 3 (aq)

Pb(NO 3 ) 2 (aq)+ KI(aq) PbI 2 (s)+ KNO 3 (aq) E. Double Replacement n Products: switch negative ions one product must be insoluble (check solubility table) NaNO 3 (aq)+ KI(aq) N.R. 2 2

Acid-Base n Reactants are an Acid and a Base n Products are Water and some ionic salt n Special kind of double replacement n HA + BOH BA + H 2 O HCl + NaOH NaCl + H 2 O