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The AP Chemistry Examination required students to write equations for 5 reactions choosen from a list of 8 options .  The reactions and equations for this question  from 1988 to 1995 are identified below.  This information is reproduced from the handouts available at 

http://www.shs.nebo.edu/Faculty/Haderlie/apchem/apchem.html

YEAR 
REACTIONS 
EQUATIONS 

1995

(a) Ethanol is burned in oxygen. 
(b) Solid barium oxide is added to distilled water. 
(c) Chlorine gas is bubbled into a cold, dilute solution of potassium hydroxide. 
(d) A solution of iron(II) nitrate is exposed to air for an extended period of time. 
(e) Excess concentrated sulfuric acid is added to solid calcium phosphate. 
(f) Hydrogen sulfide gas is bubbled into a solution of mercury(II) chloride. 
(g) Solid calcium hydride is added to distilled water. 
(h) A bar of zinc metal is immersed in a solution of copper(II) sulfate. 

(a) C₂H₅OH + O₂ --> CO₂ + H₂O 

(b) BaO + H₂O --> Ba²⁺ + OH^-

(c) Cl₂ + OH^- --> Cl^- + ClO^- +  (H₂O) 

(d) Fe²⁺ + O₂ (+ H₂O) --> Fe₂O₃ or FeO(OH) or Fe(OH)₃

(e) H₂SO₄ + Ca₃(PO₄)₂ --> H₃PO₄ + CaSO₄

(f) H₂S + Hg²⁺ --> HgS + H⁺ or H₂S + HgCl₂ --> HgS + H⁺ + Cl^-

(g) CaH₂ + H₂O --> Ca²⁺ + OH^- (or Ca(OH)₂) + H₂

(h) Zn + Cu²⁺ --> Zn²⁺ + Cu 

1994

(a) Excess sodium cyanide solution is added to a solution of silver nitrate. 
(b) Solutions of manganese(ee) sulfate and ammonium sulfide are mixed. 
(c) Phosphorus(v) oxide powder is sprinkled over distilled water. 
(d) Solid ammonium carbonate is heated. 
(e) Carbon dioxide gas is bubbled through a concentrated solution of potassium hydroxide. 
(f) A concentrated solution of hydrochloric acid is added to solid potassium permanganate. 
(g) A small piece of sodium metal is added to distilled water. 
(h) A solution of potassium dichromate is added to an acidified solution of iron (II) chloride. 

(a) CN^- + Ag⁺ --> Ag(CN)₂^-
(b) Mn⁺² + S^2- --> MnS 

(c) P₄O₁₀ (or P₂O₅) + H₂O --> H₃PO₄

(d) (NH₄)₂CO₃ --> NH₃ + H₂O + CO₂

(e) CO₂ + OH^- --> HCO₃^-  or  CO₂ + OH^- --> CO₃^2-

(f) H⁺ + Cl^- + KMnO₄ --> K⁺ + Mn²⁺ + Cl₂ + H₂O 

(g) Na + H₂O --> H₂O + Na⁺ + OH^-

(h) Cr₂O₇^2- + Fe²⁺ + H⁺ --> Cr³⁺ + Fe³⁺ + H₂O 
 

1993

(a) A strip of copper is immersed in dilute nitric acid. 
(b) Potassium permanganate solution is added to an acidic solution of hydrogen peroxide. 
(c) Concentrated hydrochloric acid is added to solid manganese(II) sulfide. 
(d) Excess chlorine gas is passed over hot iron filings. 
(e) Water is added to a sample of solid magnesium nitride. 
(f) Excess sulfur dioxide gas is bubbled through a dilute solution of potassium hydroxide. 
(g) Excess concentrated ammonia solution is added to a suspension of silver chloride. 
(h) Solutions of tri-potassium phosphate and zinc nitrate are mixed. 

(a) Cu + H⁺ + NO₃^- --> Cu²⁺ + NO + H₂O 

(b) MnO₄^- + H₂O₂ --> Mn²⁺ + O₂ + H₂O 

(c) H⁺ + MnS --> H₂S + Mn²⁺

(d) Fe + Cl₂ --> FeCl₃

(e) Mg₃N₂ + H₂O --> Mg(OH)₂ + NH₃

(f) SO₂ + OH^- --> HSO₃^-

(g) AgCl + NH₃ --> Ag(NH₃)⁺ + Cl^-

(h) Zn²⁺ + PO₄^3- --> Zn₃(PO₄)₂
 

1992

(a) An excess of sodium hydroxide solution is added to a solution of magnesium nitrate. 
(b) Solid lithium hydride is added to water. 
(c) Solutions of ammonia and hydrofluoric acid are mixed. 
(d) A piece of aluminum metal is added to a solution of silver nitrate. 
(e) A solution of potassium iodide is electrolyzed. 
(f) Solid potassium oxide is added to water. 
(g) An excess of nitric acid solution is added to a solution of tetraamminecopper(II) sulfate. 
(h) Carbon dioxide gas is bubbled through water containing a suspension of calcium carbonate. 

(a) OH^- + Mg⁺² -----> Mg(OH)₂

(b) LiH + H₂O -----> Li⁺ + OH^- + H₂

(c) NH₃ + HF -----> NH₄⁺ + F^-

(d) Al + Ag⁺ -----> Al⁺³ + Ag 

(e) I^- + H₂O -----> I₂ + H₂ + OH^-

(f) K₂O + H₂O -----> K⁺ + OH^-

(g) H⁺ + Cu(NH₃)₄⁺² -----> Cu⁺² + NH₄⁺

(h) CaCO₃ + H₂O (or H₂CO₃) -----> Ca⁺² + HCO₃^-
 

1991

(a) Solid aluminum oxide is added to a solution of sodium hydroxide. 
(b) Solid calcium oxide is heated in the presence of sulfur trioxide gas. 
(c) Equal volumes of 0.1-molar sulfuric acid and 0.1-molar potassium hydroxide are mixed. 
(d) Calcium metal is heated strongly in nitrogen gas. 
(e) Solid copper(II) sulfide is heated strongly in oxygen gas. 
(f) A concentrated solution of hydrochloric acid is added to powdered manganese dioxide and gently heated. 
(g) A concentrated solution of ammonia is added to a solution of zinc iodide. 
(h) A solution of copper(II) sulfate is added to a solution of barium hydroxide. 

(a) Al₂O₃ + OH^- -----> Al(OH)₄^-

(b) CaO + SO₃ -----> CaSO4 

(c) H⁺ + OH^- -----> H₂O 

(d) Ca + N₂ -----> Ca₃N₂

(e) CuS + O₂ -----> CuO + SO₂

(f) H⁺ + Cl^- + MnO₂ -----> Mn⁺² + Cl₂ + H₂O 

(g) NH₃ + Zn⁺² -----> Zn(NH₃)₄⁺²

(h) Cu⁺² + SO₄^-2 + Ba⁺² + OH^- -----> Cu(OH)₂ + BaSO₄
 
 

1990

(a) Solutions of sodium iodide and lead nitrate are mixed. 
(b) A solution of ammonia is added to a solution of ferric chloride. 
(c) A solution of hydrogen peroxide is heated. 
(d) Solutions of silver nitrate and sodium chromate are mixed. 
(e) Hydrogen sulfide gas is bubbled through a solution of potassium hydroxide. 
(f) Solid dinitrogen pentoxide is added to water. 
(g) A piece of solid bismuth is heated strongly in oxygen. 
(h) A strip of copper metal is added to a concentrated solution of sulfuric acid. 

(a) Pb⁺² + 2I^- -----> PbI₂

(b) Fe⁺³ + NH₃ + H₂O -----> Fe(OH)₃ + NH₄⁺

(c) H₂O₂ -----> H₂O + O₂

(d) Ag⁺ + CrO₄^-2 -----> Ag₂CrO₄

(e) H₂S + OH^- -----> HS^- + H₂O 

(f) N₂O₅ + H₂O -----> H⁺ + NO₃^-

(g) Bi + O₂ -----> Bi₂O₃

(h) Cu + H⁺ + HSO₄^- -----> Cu⁺² + SO₂ + H₂O 
 
 

1989

(a) Solutions of zinc sulfate and sodium phosphate are mixed. 
(b) Solutions of silver nitrate and lithium bromide are mixed. 
(c) A stream of chorine gas is passed through a solution of cold, dilute sodium hydroxide. 
(d) Excess hydrochloric acid solution is added to a solution of potassium sulfide. 
(e) A solution of tin(II) chloride is added to an acidified solution of potassium permanganate. 
(f) A solution of ammonium thiocyanate is added to a solution of iron(II) chloride. 
(g) Sample of boron trichloride gas and ammonia gas are mixed. 
(h) Carbon disulfide vapor is burned in excess oxygen. 

(a) Zn⁺² + PO₄^-3 -----> Zn₃(PO₄)₂

(b) Ag⁺ + Br^- -----> AgBr 

(c) Cl₂ + OH^- -----> ClO^- + Cl^- + H₂O 

(d) H⁺ + SO₃^-2 -----> H₂O + SO₂ or H₂SO₃

(e) Sn⁺² + H⁺ + MnO₄^- -----> Sn⁺⁴ + Mn⁺² + H₂O 

(f) Fe⁺³ + SCN^- -----> Fe(SCN)⁺² or Fe(SCN)₆^-3

(g) BCl₃ + NH₃ -----> Cl₃BNH₃

(h) CS₂ + O₂ -----> CO₂ + SO₂ (or SO₃) 
 
 

1988

(a) A solution of potassium iodide is added to an acidified solution of potassium dichromate. 
(b) A solution of sodium hydroxide is added to a solution of ammonium chloride. 
(c) A strip of magnesium is added to a solution of silver nitrate. 
(d) Solid potassium chlorate is heated in the presence of manganese dioxide as a catalyst. 
(e) Dilute hydrochloric acid is added to a solution of potassium carbonate. 
(f) Sulfur trioxide gas is added to excess water. 
(g) Dilute sulfuric acid is added to a solution of barium chloride. 
(h) A concentrated solution of ammonia is added to a solution os copper(II) chloride. 

(a) H⁺ + I^- + Cr₂O₇^2- -----> I₂ + Cr⁺³ + H₂O 

(b) OH^- + NH₄⁺ -----> H₂O + NH₃

(c) Mg + Ag⁺ -----> Mg⁺² + Ag 

(d) KClO₃ -----> KCl + O₂ (with MnO₂ as a catalyst) 

(e) H⁺ + CO₃^-2 -----> CO₂ + H₂O (or H₂CO₃ or HCO₃^-) 

(f) SO₃ + H₂O -----> H⁺ + HSO₄^-

(g) SO₄^-2 + Ba⁺² -----> BaSO₄ (or HSO₄^- + Ba⁺² -----> BaSO₄ + H⁺) 

(h) Cu⁺² + NH₃ -----> Cu(NH₃)₄⁺²