Descriptive chemistry

This part requires that you write 5 reactions equations (chosen from 8) in net ionic form. There will always be a reaction. The products will be different from the reactants in every case

Each reaction is worth 3 points. One ( l ) point is given for writing the reactant formulas correctly. A maximum of two (2) points is given as (full or partial) credit for correctly predicting the products. Remember, to receive this credit the equation must be in net ionic form.

Write out only 5 reactions. Even if you do more, the first 5 will be scored. This part is worth 15 points, and should be given only 10-15 minutes.

The equations should not be balanced, and the states are not required. However balancing the equations and putting in the states may help predict the products, and there is no rule against it.

 

1. General Considerations

            a. Common polyatomic anions and cations.

            b. Diatomics

            c. Solubility

                        1. SOLUBLE all salts containing NH4+ , and the Group 1A cations. (Alkali metals)

                        2. SOLUBLE All salts containing Nitrate (NO3-), acetate (C2H3O2-), perchlorate (ClO4-)

`                       3. INSOLUBLE  Salts containing Ag+, Pb+2, and Hg+2,

                        4. SOLUBLE all halogen ions (i.e. Cl-) Except for rule 3.

                        5. SOLUBLE All sulfates except rule 3 and CaSO4 BaSO4, and SrSO4

                                6. INSOLUBLE Carbonates, chromates, hydroxides, oxides, phosphates, and sulfides

                                    a) Group 2A chromates except BaCrO4 are soluble

                                    b) Group 2A hydroxides except Mg(OH)2 are soluble.

            d. Soluble salts are shown as dissociated ions, insoluble as a formula.

            e. Strong acids and are shown dissociated, weak are shown together as a single formula.

            f. Eliminate the spectator ions.

            g. Use solubility to predict reaction.

2. No change in oxidation state

a)      Replacement reactions

                        1. Precipitation

                        2. Neutralization

                        3. Hydrolysis Water + salt ®  Acid (Weak?) + base (weak?)

b)      Oxides

      1. Metal oxide + water ® hydroxides

      2. Nonmetal oxides and water ® acids.

      3. Metal oxide + non metal oxide ® salt

c)      Decomposition- opposite of above

      1. Hydroxide ® metal oxide and water.

      2. Acid ® water and non metal oxides.(Especially carbonic acid)

      3. Salts ®  nonmetal oxide + metal oxide

d)      Complex ions and Coordination compounds.

      1. 3 common Lewis bases (NH3 , CN-, and OH-)

      2. Not graded on the number of ligands attached.

      3. Are graded on the charge on the ion.

      4. Acids will break up by taking away the base.

e)      Lewis acids and bases (Especially BF3)

3. Redox reactions.

            Oxidizing Agents

 

Reducing Agents

Oxidizing Agent

Product of the reaction

 

Reducing Agent

Product of the reaction

MnO4- in acid

Mn+2

 

Halogen in dilute base

Hypohalite ClO-

MnO4- In base or neutral

MnO2

 

Halogen in concentrated base

Halite ClO2-

MnO2 in acid

Mn+2

 

 

 

HNO3 concentrated

NO2

 

Nitrite ions (NO2-)

Nitrate ions (NO3-)

HNO3 dilute

NO

 

 

 

H2SO4 hot, concentrated

SO2

 

Sulfite ions (SO3-2) or SO2

Sulfate ions (SO4-2)

Halogens

Halide ions

 

Halide ions

Halogens

HClO4

Cl-

 

Free metals

Metal ions

Peroxides (Na2O2, H2O2)

NaOH, HOH

 

 

 

 Dichromate ion Cr2O7-2

Cr+3

 

 

 

Metal ions

free metals

 

 

 

 

2. Recognized by change in oxidation state.

3. “Added acid”

4. Use the reduction potential table on the front cover.

5. Redox can replace.

6. Combination oxidizing agent of one element will react with the reducing agent of the same element to produce the free element.

            I- + IO3-  + H+  ® I2 + H2O

7. Decomposition.

            a) peroxides to oxides

            b) Chlorates to chlorides

            c) Electrolysis into elements.

            d) carbonates to oxides

1.      A piece of solid bismuth is heated strongly in oxygen.

2.      A strip or copper metal is added to a concentrated solution of sulfuric acid.

3.      Solutions of zinc sulfate and sodium phosphate are mixed.

4.      Solutions of silver nitrate and lithium bromide are mixed.

5.      A stream of chlorine gas is passed through a solution of cold3 dilute sodium hydroxide.

6.      Excess hydrochloric acid solution is added to a solution of potassium sulfite.

7.      A solution of tin ( II ) chloride is added to an acidified solution of potassium permanganate

8.      A solution of ammonium thiocyanate is added to a solution of iron (III) chloride.

9.      Samples of boron trichloride gas and ammonia gas are mixed.

10. Carbon disulfide vapor is burned in excess oxygen.

11. A solution of potassium iodide is added to an acidified solution of potassium dichromate.

12. A solution of sodium hydroxide is added to a solution of ammonium chloride.

13. A strip of magnesium is added to a solution of silver nitrate.

14. Solid potassium chlorate Is heated in the presence of manganese dioxide as a catalyst

15. Dilute hydrochloric acid Is added to a solution of potassium carbonate.

16. Sulfur trioxide gas is added to excess water.

17. Dilute sulfuric acid is added to a solution of barium chloride.

18. A concentrated solution of ammonia is added to a solution of copper (II) chloride.

19. Solid calcium is added to warm water.

20. Powdered magnesium oxide is added to a container of carbon dioxide gas.

21. Gaseous hydrogen sulfide is bubbled through a solution of nickel (II) nitrate.

22. Excess concentrated sodium hydroxide solution is added to solid aluminum hydroxide.

23. Excess potassium hydroxide solution is added to a solution of potassium dihydrogen phosphate.

24. Hydrogen peroxide solution is added to a solution of iron (II) sulfate.

25. Propanol is burned completely in air.

26. A piece of lithium metal is dropped into a container of nitrogen gas.

27. Dilute hydrochloric acid is added to a solution of potassium sulfite.

28. Solid sodium oxide is added to water.

29. A solution of sodium sulfide is added to a solution of zinc nitrate.

30. A solution of ammonia is added to a dilute solution of acetic acid.

31. A piece of iron is added to a solution of Iron (III) sulfate.

32. Chlorine gas is bubbled into a solution of potassium iodide.

33. Sodium metal is added to water.

34. Dilute sulfuric acid Is added to a solution of lithium hydrogen carbonate.

35. Excess concentrated potassium hydroxide solution Is added to a precipitate of zinc hydroxide.

36. The gases boron trifluoride and ammonia are mixed

37. A solution of tin (II) chloride Is added to a solution of iron (III) sulfate.

38. An acidified solution of sodium permanganate is added to a solution of sodium sulfite.

39. Hydrogen gas is passed over hot iron(III)oxide.

40. Solutions of potassium iodide and potassium iodate are mixed in acid solution.

41. Dilute sulfuric acid is added to solid calcium fluoride.

42. Solid ammonium carbonate is heated

43. Methane gas is mixed with an excess of chlorine gas

44. Concentrated hydrochloric acid solution is added to solid manganese (IV) oxide and the reactants are heated.

45. Gaseous SiH4 is burned in oxygen.

46. Equal volumes of 0.1 molar hydrochloric acid and 0.1 molar disodium monohydrogen phosphate are mixed.

47. Hydrogen sulfide gas is bubbled through a solution of lead (II) nitrate.

48. Solid zinc strips are added to a solution of copper sulfate.

49. Solid lithium oxide is added to excess water.

50. Copper (II) sulfide is oxidized by dilute nitric acid

51. Silver chloride is dissolved in excess ammonia solution.

52. Dilute sulfuric acid is added to a solution of barium acetate.

53. Ammonium chloride crystals are added to a solution of sodium hydroxide

54. Solid phosphorus pentachloride is added to excess water.

55. A solution of hydrogen peroxide is catalytically decomposed.

56. Powdered Iron is added to a solution of iron(III) sulfate.

57. Chlorine gas is bubbled into a solution of sodium bromide.

58. A precipitate is formed when solutions of trisodium phosphate and calcium chloride are mixed.

59. Solid calcium oxide is exposed to a stream of carbon dioxide gas.

60. Dinitrogen trioxide gas is bubbled into water.

61. Sodium hydrogen carbonate is dissolved in water.

62. Pellets of lead are dropped into hot sulfuric acid

63. Potassium, permanganate solution Is added to a solution of oxalic acid, H2C2O4, acidified with a few drops of sulfuric acid.

64. Magnesium turnings are added to a solution of iron (III) chloride.

65. Ethyl acetate Is treated with a solution of sodium hydroxide.

66. A suspension of zinc hydroxide Is treated with concentrated sodium hydroxide solution.

67. A concentrated solution of ammonia is added to a suspension of zinc hydroxide.

68. Hydrogen peroxide is added to an acidified solution of sodium bromide.

69. Dilute hydrochloric acid is added to a dilute solution of mercury (I) nitrate

70. Magnesium metal is burned in nitrogen gas.

71. Sulfur dioxide gas is passed over solid calcium oxide.

72. Lead foil is immersed in silver nitrate solution.

73. A solution of ammonium sulfate is added to a saturated solution of barium hydroxide.

74. Acetic acid solution is added to a solution of sodium hydrogen carbonate.

75. Solid sodium dichromate is added to an acidified solution of sodium iodide.

76. A drop of potassium thiocyanate is added to a solution of iron (III) chloride.

77. Ethanol is completely burned in air.

78. Solutions of sodium fluoride and dilute hydrochloric acid are mixed.

79. A saturated solution of barium hydroxide is mixed with a solution of iron (III) sulfate.

80. A solution of ammonium sulfate is added to a potassium hydroxide solution.

81. Carbon dioxide gas is bubbled through a concentrated solution of sodium hydroxide.

82. Solid copper is added to a dilute nitric acid solution.

83. Chlorine gas is bubbled into a cold solution of dilute sodium hydroxide.

84. A solution of potassium permanganate is mixed with an alkaline solution of sodium sulfite.

85. Methyl Iodide is heated with a solution of sodium hydroxide.

86. A solution of copper (II) sulfate is electrolyzed using inert electrodes.

87. Hydrogen sulfide gas is bubbled through excess potassium hydroxide solution.

88. Solutions of silver nitrate and sodium chromate are mixed.

89. Sodium hydroxide solution is added to a precipitate of aluminum hydroxide in water.

90. Solid sodium sulfite is added to water.

91. A solution of formic acid, HCOOH, Is oxidized by an acidified solution of potassium dichromate.

92. Ammonia gas and carbon dioxide gas are bubbled into water.