1. REACTION PREDICTION Pre-AP CHEMISTRY

2. Reactants  Products The arrow means “yields” or “produces”

3. (s) = solid (g)= gas (l)= liquid (aq)= aqueous (dissolved in water)  = reversible reaction = catalyst (in this case, Pt is the catalyst) = heat is added = heat is added

4. Practice “translating” a word equation: Solid zinc metal reacts with aqueous copper(II) sulfate to produce solid copper metal and aqueous zinc sulfate.
Zn(s) + CuSO4(aq)  Cu(s) + ZnSO4(aq)

5. Balancing Equations *Balancing is a trial and error process and is best done in pencil!! *We balance an equation so that the reactants and products each have the same number of atoms of each element (conservation of mass). *We must correctly write the formulas for all reactants and products before we balance.

6. Coefficients = Numbers placed in front of reactants and products 2H2 + O2  2H2O This means that 2 moles or molecules of hydrogen gas react with 1 mole or molecule of oxygen gas to produce 2 moles or molecules of water. The coefficients must be in the lowest ratio.

7. Hints:. Balance elements one at a time
Hints: *Balance elements one at a time. *Balance polyatomic ions that appear on both sides of the equation as single units. (Ex. Count sulfate ions, not sulfur and oxygen separately) *Balance H and O last.

8. Zn + HCl  ZnCl2 + H2
Zn + 2HCl  ZnCl2 + H2

9. Al2(SO4)3 + Ca(OH)2  Al(OH)3 + CaSO4

10. K + H2O  KOH + H2
2K + 2H2O  2KOH + H2

11. CH4 + O2  CO2 + H2O
CH4 + 2O2  CO2 + 2H2O

12. Fe + Cl2  FeCl3
2Fe + 3Cl2  2FeCl3

13. C6H14 + O2  CO2 + H2O
2C6H O2  12CO H2O

14. Al4C3 + H2O  CH4 + Al(OH)3
Al4C H2O  3CH4 + 4Al(OH)3

15. Balance the following chemical equations.
___ Ca + ____ H2O  ____Ca(OH)2+____H2
Ca + 2 H2O  Ca(OH)2 + H2
2. ____Cu2S + _____O2  ____Cu2O + ______SO2
2 Cu2S + 3 O2  2 Cu2O + 2SO2
3. _____MnO2 + _____HCl  ______MnCl2 + ______H2O + _____Cl2
MnO2 + 4 HCl  MnCl2 + 2H2O + Cl2
4. _____NH4NO3 + _____NaOH  _____NH3 + _____H2O + _____NaNO3
NH4NO3 + NaOH  NH3 + H2O + NaNO3

16. 3 Zn(OH)2 + 2 H3PO4  Zn3(PO4)2 + 6H2O 3 CO + Fe2O3  2 Fe + 3 CO2
5. ____Fe(OH)3  _____Fe2O3 + _____H2O
2Fe(OH)3  Fe2O3 + 3H2O
6. _____C3H6 + _____O2  _____CO2 + _____H2O
2C3H6 + 9O2  6CO2 + 6H2O
7. __Zn(OH)2 + __H3PO4  __Zn3(PO4)2 + ___H2O
3 Zn(OH)2 + 2 H3PO4  Zn3(PO4)2 + 6H2O
8. _____CO + _____Fe2O3  _____Fe + _____CO2
3 CO + Fe2O3  2 Fe + 3 CO2
_ NH4Cl + __Ca(OH)2  ___NH3 + ___H2O + __CaCl2
2NH4Cl + Ca(OH)2  2 NH3 + 2 H2O + CaCl2
___HC2H3O2 + ___NaHCO3  __CO2 + __NaC2H3O2 + __H2O
HC2H3O2 + NaHCO3  CO2 + NaC2H3O2 + H2O

17. Write a balanced chemical equation for each of the following reactions
Write a balanced chemical equation for each of the following reactions. Include physical state symbols. 1. Copper metal heated with oxygen gives solid copper(II) oxide.
2Cu(s) + O2(g)  2CuO(s)

18. 2. Mixing ammonium nitrate and sodium hydroxide solutions gives aqueous sodium nitrate, ammonia gas, and water.
NH4NO3(aq) + NaOH(aq) 
NaNO3(aq) + NH3(g) + H2O(l)

19. 3. Mercury(II) nitrate solution reacts with potassium iodide solution to give a mercury(II) iodide precipitate and potassium nitrate solution.
Hg(NO3)2(aq) + 2KI(aq)  HgI2(s) + 2KNO3(aq)

20. 4. Solutions of acetic acid and lithium hydroxide produce water and aqueous lithium acetate.
HC2H3O2(aq) + LiOH(aq)  H2O(l) + LiC2H3O2(aq)

21. 5. Heating solid potassium chlorate in the presence of manganese dioxide catalyst produced potassium chloride and oxygen gas.
2KClO3(s) MnO2 2KCl(s) + 3O2(g)

22. DECOMPOSITION REACTIONS -Reaction where a compound breaks down into two or more elements or compounds. Heat, electrolysis, or a catalyst is usually necessary.

23. A compound may break down to produce two elements.
Ex. Molten sodium chloride is electrolyzed.
2NaCl 2Na + Cl2

24. A compound may break down to produce an element and a compound.
Ex. A solution of hydrogen peroxide is decomposed catalytically.
2H2O2  2H2O + O2

25. A compound may break down to produce two compounds.
Ex. Solid magnesium carbonate is heated MgCO3 MgO + CO2

26. Metallic carbonates break down to yield metallic oxides and carbon dioxide.
K2CO3  K2O + CO2

27. Metallic chlorates break down to yield metallic chlorides and oxygen.
2RbClO3  2RbCl + 3O2

28. Metallic sulfites break down to yield metallic oxides and sulfur dioxide.
BaSO3  BaO + SO2

29. Hydrogen peroxide decomposes into water and oxygen.

30. Sulfurous acid decomposes into water and sulfur dioxide.

31. Carbonic acid decomposes into water and carbon dioxide.

32. Hydrated salts decompose into the salt and water
Sodium carbonate monohydrate is heated.
Na2CO3.H2O Δ Na2CO3 + H2O

33. Complete and balance the following reactions:

34. 1. ZnCO3 
ZnCO3  ZnO + CO2

35. 2. KClO3 
2KClO3 2KCl + 3O2

36. 3. HgO 
2HgO 2Hg + O2

37. 4. H2CO3 
H2CO3 H2O + CO2

38. 2NaCl electricity > 2Na + Cl2

39. 6. H2SO3 
H2SO3 H2O + SO2

40. 7. CaCO3
CaCO3CaO + CO2

41. 2H2O electricity > 2H2 + O2

42. 9. Na2SO4.10H2O 
Na2SO4.10H2O  Na2SO4 +10H2O

43. 10. H2O2 MnO2 >
2H2O2 MnO2 >2H2O + O2

44. 11. CuSO4.5H2O 
CuSO4.5H2O  CuSO4 + 5H2O

45. ADDITION REACTIONS -also called synthesis, combination or composition reactions -Two or more elements or compounds combine to form a single product.

46. -A Group IA or IIA metal may combine with a nonmetal to make a salt.
Ex. A piece of lithium metal is dropped into a container of nitrogen gas.
6Li + N2  2Li3N

47. -Two nonmetals may combine to form a molecular compound. C + O2  CO2

48. -Two compounds combine to form a single product.
Sulfur dioxide gas is passed over solid calcium oxide SO2 + CaO  CaSO3

49. -A metallic oxide plus carbon dioxide yields a metallic carbonate
-A metallic oxide plus carbon dioxide yields a metallic carbonate. (Carbon keeps the same oxidation state)
Li2O + CO2  Li2CO3

50. -A metallic oxide plus sulfur dioxide yields a metallic sulfite
-A metallic oxide plus sulfur dioxide yields a metallic sulfite. (Sulfur keeps the same oxidation state)
K2O + SO2  K2SO3

51. -A metallic oxide plus water yields a metallic hydroxide
-A metallic oxide plus water yields a metallic hydroxide CaO + H2O Ca(OH)2

52. -A nonmetallic oxide plus water yields an acid. CO2 + H2O  H2CO3

53. Complete and balance the following equations:

54. 1. Li + I2 
2Li + I2  2LiI

55. 2. Mg + N2 
3Mg + N2  Mg3N2

56. 3. SO3 + H2O 
SO3 + H2O  H2SO4

57. 4. Sr + S 
Sr + S  SrS

58. 5. Mg + O2 
2Mg + O2  2MgO

59. 6. Ag + O2 
4Ag + O2  2Ag2O

60. 7. Na2O + H2O 
Na2O + H2O  2NaOH

61. 8. SO2 + H2O 
SO2 + H2O H2SO3

62. 9. BaO + CO2
BaO + CO2 BaCO3

63. 10. CaO + SO2 
CaO + SO2  CaSO3

64. Double Replacement (metathesis)
Two compounds react to form two new compounds.
All double replacement reactions must have a "driving force" that removes a pair of ions from solution.
Ions keep their same charges as reactants and products.

65. Formation of a precipitate: A precipitate is an insoluble substance formed by the reaction of two aqueous substances. Two ions bond together so strongly that water can not pull them apart.

68. SOLUBILITY SONG Nitrates and Group One and Ammonium,
To the tune of “ My Favorite Things” from “The Sound of Music”
Nitrates and Group One and Ammonium,
These are all soluble, a rule of thumb.
Then you have chlorides, they’re soluble fun,
All except Silver, Lead, Mercury I.
Then you have sulfates, except for these three:
Barium, Calcium and Lead, you see.
Worry not only few left to go still.
We will do fine on this test. Yes, we will!
Then you have the---
Insolubles
Hydroxide,
Sulfide and Carbonate and Phosphate,
And all of these can be dried!

69. Ex. Solutions of silver nitrate and lithium bromide are mixed.
AgNO3(aq) + LiBr(aq) AgBr(s) + LiNO3(aq)

70. Formation of a gas: Gases may form directly in a double replacement reaction or can form from the decomposition of a product such as H2CO3 or H2SO3. (Don't leave carbonic or sulfurous acids, or ammonium hydroxide as products of double replacement reactions, decompose them!)

71. 2HCl(aq) + K2SO3(aq) 2KCl(aq) + H2O(l) + SO2(g)
Ex. Excess hydrochloric acid solution is added to a solution of potassium sulfite.
2HCl(aq) + K2SO3(aq)
2KCl(aq) + H2O(l) + SO2(g)

72. NaOH(aq)+ NH4Cl(aq)  NH3(g) + H2O(l) + NaCl(aq)
Ex. A solution of sodium hydroxide is added to a solution of ammonium chloride.
NaOH(aq)+ NH4Cl(aq) 
NH3(g) + H2O(l) + NaCl(aq)

73. Formation of a molecular substance: When a molecular substance such as water or acetic acid is formed, ions are removed from solution and the reaction "works".

74. LiOH(aq) + HBr(aq)  LiBr(aq) + H2O
Ex. Dilute solutions of lithium hydroxide and hydrobromic acid are mixed.
LiOH(aq) + HBr(aq) 
LiBr(aq) + H2O

75. Complete and balance the following equations:

76. 2NaOH + CuSO4  Na2SO4 + Cu(OH)2(s)

77. NH4I + AgNO3  NH4NO3 + AgI(s)

78. K2CO3 + Ba(OH)2  2KOH + BaCO3(s)

79. 4. KOH + HI
KOH + HIKI + H2O(l)

80. 5. K2CO3 + HNO3 
K2CO3 + 2HNO3 
2KNO3 + H2O + CO2

81. (NH4)2SO4 + BaCl2  2NH4Cl + BaSO4(s)

82. Na2S + NiSO4  NiS(s) + Na2SO4

83. Pb(NO3)2 + 2KBr  PbBr2(s) + 2KNO3

84. Fe2(SO4)3 + 3Ba(OH)2  2Fe(OH)3(s) + 3BaSO4(s)

85. Hg2(NO3)2 + 2KI  2KNO3 + Hg2I2(s)

86. Single Replacement Reaction where one element displaces another in a compound. One element is oxidized and another is reduced A + BC  B + AC

88. Active metals replace less active metals or hydrogen from their compounds in aqueous solution. Use an activity series to determine the activity of metal.

90. Ex. Magnesium turnings are added to a solution of iron(III) chloride.
3Mg(s) + 2FeCl3(aq)  2Fe(s) + 3MgCl2(aq)

91. Ex. Sodium is added to water.
2Na(s) + 2H2O(l)
2NaOH(aq) + H2(g)
Reactions of Alkali metals

92. Ex. Fe + H2O
Fe + H2O no reaction

93. Active nonmetals replace less active nonmetals from their compounds in aqueous solution. Each halogen will displace heavier halogens from their binary salts.

94. Activity Series of Nonmetals Most Active F2 Cl2 Br2 Least Active I2

95. Ex. Chlorine gas is bubbled into a solution of potassium iodide.
Cl2(g) + 2KI(aq) 
I2(s) + 2KCl(aq)

96. Ex. I2 + KCl 
I2 + KCl  no reaction

97. Complete and balance the following equations:

98. 1. Zn + HCl 
Zn +2 HCl ZnCl2 + H2

99. 2. Br2 + NaCl 
Br2 + NaCl  No Reaction

100. 3. F2 + NaBr 
F2 + 2NaBr 2NaF + Br2

101. 4. Al + CuSO4 
2Al + 3CuSO4 
Al2(SO4)3 + 3Cu

102. 5. Cu + AgNO3 
Cu + 2AgNO3 
Cu(NO3)2 + 2Ag

103. 6. Cd + CuSO4 
Cd + CuSO4 
CdSO4 + Cu

104. 7. K + H2O 
2K + 2H2O 
2KOH + H2

105. 8. Mg + H2SO4 
Mg + H2SO4 
MgSO4 + H2

106. 9. Ag + HCl 
Ag + HCl No Rxn

107. 10. I2 + KCl 
I2 + KCl No Rxn

108. 11. Ca + H2O 
Ca + 2H2O Ca(OH)2 + H2

109. 12. Zn + H2O 
Zn + H2O No Rxn

110. COMBUSTION REACTIONS

111. In the presence of excess oxygen, most hydrocarbons and alcohols can undergo complete combustion reactions to form carbon dioxide and water. The only tricky part is balancing the reaction. Balance the C first, H second, and O third.

112. Ex. Ethane (C2H6) burns in air.
2C2H6 + 7O2  4CO2 + 6H2O

113. Ethanol (C2H5OH) burns
C2H5OH + 3O2  2CO2 + 3H2O

114. Complete and balance the reactions for the combustion of the following compounds:

115. 1. CH4
CH4 + 2O2  CO2 + 2H2O

116. 2. C2H2
2C2H2 + 5 O2  4CO2 + 2H2O

117. 3. CH3OH
2CH3OH + 3O2  2CO2 + 4H2O

118. 4. C6H12O6
C6H12O6 + 6O2  6CO2 + 6H2O

119. 5. C8H18
2C8H O2  16CO2 + 18H2O

120. 6. C3H8
C3H8 + 5O2  3CO2 + 4H2O

121. 7. C6H6
2C6H6 + 15O2  12CO2 + 6H2O

122. 8. C2H4
C2H4 + 3O2  2CO2 + 2H2O

123. 9. C35H72
C35H O2  35CO2 +36 H2O

124. 10. C3H7OH
2C3H7OH + 9O2  6CO2 + 8H2O

125. SYNTHESIS AND DECOMPOSITION REACTIONS

126. Complete and balance the following equations:

127. 1. Sr + O2 
2Sr + O2 2SrO

128. 2. Na + O2 
4Na + O2 2Na2O

129. 3. K + Cl2 
2K + Cl2 2KCl

130. 4. Ca + F2 
Ca + F2 CaF2

131. 5. sodium + iodine 
2Na + I2 2NaI

132. 6. magnesium + oxygen 
2Mg + O2 2MgO

133. 7. hydrogen + chlorine 
H2 + Cl2  2HCl

134. 8. silver + sulfur 
2Ag + S  Ag2S

135. 9. calcium oxide + water 
CaO + H2O  Ca(OH)2

136. 10. sulfur trioxide + water 
SO3 + H2O  H2SO4

137. 11. MgBr2
MgBr2 Mg + Br2

138. 12. AlCl3 
2AlCl3 2Al + 3Cl2

139. 13. H2O 
2H2O 2H2 + O2

140. 14. KI 
2KI 2K + I2

141. 15. NaCl 
2NaCl 2Na + Cl2

142. 16. nickel(II) chlorate 
Ni(ClO3)2  NiCl2 + 3O2

143. SINGLE AND DOUBLE REPLACEMENT REACTIONS

144. Write and balance the following reactions:

145. Zn(s) + CuSO4(aq) ZnSO4(aq) + Cu(s)

146. Cl2(g) + 2KI(aq) 2KCl(aq) + I2(s)

147. Ni(s) + MgSO4(aq) No Reaction

148. Br2(l) + CaCl2(aq) No Rxn

149. 5. zinc + copper(II) nitrate 
Zn(s) + Cu(NO3)2(aq)  Cu(s) + Zn(NO3)2(aq)

150. 6. calcium + hydrochloric acid 
Ca(s) + 2HCl(aq)  CaCl2(aq) + H2(g)

151. 7. copper(II) nitrate + silver 
Cu(NO3)2(aq) + Ag(s)  No Rxn

152. 8. sodium iodide + bromine 
2NaI(aq) + Br2(l)  2NaBr(aq) + I2(s)

153. 2Na(s) + 2H2O(l)  2NaOH(aq) + H2(g)
9. sodium + water 
2Na(s) + 2H2O(l)  2NaOH(aq) + H2(g)

154. FeCl2(aq) + K2S(aq)  FeS(s) + 2KCl(aq)
10. FeCl2 + K2S 
FeCl2(aq) + K2S(aq) 
FeS(s) + 2KCl(aq)

155. ZnCl2(aq) + Pb(NO3)2(aq) Zn(NO3)2(aq) + PbCl2(s)
11. ZnCl2 + Pb(NO3)2 
ZnCl2(aq) + Pb(NO3)2(aq)
Zn(NO3)2(aq) + PbCl2(s)

156. CaCl2(aq) + Na2CO3(aq)  2NaCl(aq) + CaCO3(s)
12. CaCl2 + Na2CO3 
CaCl2(aq) + Na2CO3(aq)  2NaCl(aq) + CaCO3(s)

157. (NH4)2SO4(aq) + BaCl2(aq)  2NH4Cl(aq) + BaSO4(s)
13. (NH4)2SO4 + BaCl2 
(NH4)2SO4(aq) + BaCl2(aq)  2NH4Cl(aq) + BaSO4(s)

158. 14. sodium hydroxide + acetic acid 
NaOH(aq) + HC2H3O2(aq)  NaC2H3O2(aq) + H2O(l)

159. 15. copper(II) sulfate + ammonium sulfide 
CuSO4(aq) + (NH4)2S(aq)  CuS(s) + (NH4)2SO4(aq)

160. MIXED EQUATION WORKSHEET #1 Complete the word equation, write the formula equation, balance it and identify the type of reaction. You many abbreviate as S, D, SR, DR, and C.

161. 1. Magnesium hydroxide + nitric acid 
magnesium nitrate + water
Mg(OH)2 + 2HNO3  Mg(NO3)2 + 2H2O DR

162. 2. Complete combustion of methane (CH4)
methane + oxygen 
carbon dioxide + water
CH4 + 2O2  CO2 + 2H2O
Combustion

163. 3. Chlorine + sodium bromide 
bromine + sodium chloride
Cl2 + 2NaBr  Br2 + 2NaCl
Single Replacement

164. 4. Aluminum + sulfuric acid 
aluminum sulfate + hydrogen
2Al + 3H2SO4 Al2(SO4)3 + 3H2
Single replacement

165. 5. Sulfuric acid + sodium acetate 
sodium sulfate + acetic acid
H2SO4 + 2NaC2H3O2 
Na2SO4 + 2HC2H3O2
Double replacement

166. 6. Heating calcium carbonate 
calcium oxide + carbon dioxide
CaCO3  CaO + CO2
Decomposition

167. 7. Heating mercuric oxide 
mercury + oxygen
2HgO  2Hg + O2
Decomposition

168. 8. Zinc + silver nitrate 
Zinc + silver nitrate 
zinc nitrate + silver
Zn + 2AgNO3  Zn(NO3)2 + 2Ag
Single Replacement

169. Sulfur + oxygen  sulfur dioxide S + O2  SO2 synthesis
9. Burning sulfur
Sulfur + oxygen 
sulfur dioxide
S + O2  SO2
synthesis

170. 10. Heating sodium chlorate
sodium chloride + oxygen
2NaClO3  2NaCl + 3O2
Decomposition

171. 11. Zinc chloride + ammonium sulfide 
zinc sulfide + ammonium chloride
ZnCl2 + (NH4)2S  ZnS + 2NH4Cl
double replacement

172. 12. Aluminum hydroxide + hydrochloric acid 
Aluminum hydroxide + hydrochloric acid  aluminum chloride + water
Al(OH)3 + 3HCl  AlCl3 + 3H2O
Double replacement

173. 13. Calcium + steam 
Calcium + steam 
calcium hydroxide + hydrogen
Ca + 2H2O  Ca(OH)2 + H2
Single replacement

174. carbonic acid  water + carbon dioxide H2CO3  H2O + CO2 Decomposition
14. Heating carbonic acid
carbonic acid 
water + carbon dioxide
H2CO3  H2O + CO2
Decomposition

175. 15. Electrolysis of sodium chloride 
sodium + chlorine
2NaCl  2Na + Cl2
Decomposition

176. 16. Combustion of propane (C3H8)
Propane + oxygen 
Carbon dioxide + water
C3H8 + 5O2  3CO2 +4 H2O
Combustion

177. 17. Bromine + potassium iodide 
Iodine + potassium bromide
Br2 + 2KI  I2 + 2KBr
Single Replacement

178. 18. Magnesium + hydrochloric acid 
magnesium chloride + hydrogen
Mg + 2HCl  MgCl2 + H2
Single replacement

179. 19. Sodium hydroxide + acetic acid 
sodium acetate + water
NaOH + HC2H3O2  NaC2H3O2 + H2O
Double replacement

180. 20. Burning hydrogen 
hydrogen + oxygen  water
2H2 + O2  2H2O
Synthesis or combustion

181. zinc sulfate + hydrogen Zn + H2SO4  ZnSO4 + H2 single replacement
21. Zinc + sulfuric acid 
Zinc + sulfuric acid 
zinc sulfate + hydrogen
Zn + H2SO4  ZnSO4 + H2
single replacement

182. 22. Heating magnesium carbonate
magnesium oxide + carbon dioxide
MgCO3  MgO + CO2
Decomposition

183. Sodium + chlorine  sodium chloride 2Na + Cl2  2NaCl Synthesis

184. 24. Lead(II) nitrate + sodium iodide 
lead (II) iodide + sodium nitrate
Pb(NO3)2 + 2NaI  PbI2 + 2NaNO3
Double replacement

185. 25. Silver nitrate + sodium sulfide 
silver sulfide + sodium nitrate
2AgNO3 + Na2S  Ag2S + 2NaNO3
Double replacement

186. 26. Iodine + potassium chloride 
No Reaction

187. 27. Magnesium oxide + water 
magnesium hydroxide
MgO + H2O  Mg(OH)2
synthesis

188. MIXED EQUATION WORKSHEET #2

189. Complete the word equation, write the formula equation, balance it and identify the type of reaction. You many abbreviate as S, D, SR, DR, and C.

190. 1. sodium hydrogen carbonate + hydrochloric acid 
sodium hydrogen carbonate + hydrochloric acid  sodium chloride + water + carbon dioxide
NaHCO3 + HCl  NaCl + H2O + CO2
double replacement

191. 2. Complete combustion of ethanol (C2H5OH)
Ethanol + oxygen 
carbon dioxide + water
C2H5OH + 3O2  2CO2 + 3H2O
Combustion

192. 3. sulfurous acid + magnesium hydroxide 
water + magnesium sulfite
H2SO3 + Mg(OH)2  2H2O + MgSO3
double replacement

193. 4. carbonic acid + lithium hydroxide 
water + lithium carbonate
H2CO3 + 2LiOH  2H2O + Li2CO3
Double replacement

194. 5. gold + sulfuric acid 
gold + sulfuric acid 
No Reaction

195. 6. aluminum + fluorine 
aluminum + fluorine  aluminum fluoride
2Al + 3F2  2AlF3
Synthesis

196. 7. calcium oxide + water 
calcium oxide + water 
calcium hydroxide
CaO + H2O  Ca(OH)2
Synthesis

197. 8. acetic acid + sodium hydroxide 
water + sodium acetate
HC2H3O2 + NaOH  H2O +NaC2H3O2
Double replacement

198. 9. potassium chloride + lead(II) nitrate 
potassium nitrate + lead(II) chloride
2KCl + Pb(NO3)2  2KNO3 + PbCl2
Double replacement

199. 10. carbon monoxide + oxygen 
carbon dioxide
2CO + O2  2CO2
Synthesis

200. sodium + chlorine  sodium chloride 2Na + Cl2  2NaCl Synthesis

201. 12. dinitrogen pentoxide + water 
nitric acid
N2O5 + H2O  H2N2O6 2HNO3
Synthesis

202. 13. bromine + sodium chloride 
No rxn

203. 14. potassium chloride + mercury(I) nitrate
potassium nitrate + mercury(I) chloride
2KCl + Hg2(NO3)2  2KNO3 + Hg2Cl2
Double replacement

204. 15. sulfur dioxide + water 
sulfurous acid
SO2 + H2O  H2SO3
Synthesis

205. lithium oxide + water  lithium hydroxide Li2O + H2O  2LiOH Synthesis

206. 17. heating zinc carbonate
zinc oxide + carbon dioxide
ZnCO3  ZnO + CO2
Decomposition

207. 18. silver nitrate + sodium chloride 
silver chloride + sodium nitrate
AgNO3 + NaCl  AgCl + NaNO3
Double replacement

208. 19. heating beryllium chlorate
beryllium chloride + oxygen
Be(ClO3)2  BeCl2 + 3O2
Decomposition

209. 20. electrolysis of water
water hydrogen + oxygen
2H2O  2H2 + O2
Decomposition

210. 21. complete combustion of butane (C4H10)
Butane + oxygen 
carbon dioxide + water
2C4H O2  8CO2 + 10H2O
Combustion

211. 22. iron(II) sulfate + ammonium sulfide 
iron(II) sulfide + ammonium sulfate
FeSO4 + (NH4)2S  FeS + (NH4)2SO4
Double replacement

212. 23. lithium + water
lithium + water
lithium hydroxide + hydrogen
2Li + 2H2O  2LiOH + H2
Single replacement

213. 24. potassium oxide + water
potassium hydroxide
K2O + H2O  2KOH
Synthesis

214. 25. silver + sulfur
silver + sulfur silver sulfide
2Ag + S  Ag2S
Synthesis

215. 26. sodium + water
sodium + water
sodium hydroxide + hydrogen
2Na + 2H2O  2NaOH + H2
Single replacement

216. 27. calcium hydroxide + ammonium sulfate
calcium sulfate + ammonia + water
Ca(OH)2 + (NH4)2SO4 
CaSO4 + 2NH3 + 2H2O
Double replacement

217. NET IONIC EQUATIONS

218. Net ionic equations show only the species actually involved in the reaction. As you first learn to write net ionic equations, you will write three different equations for each reaction.

219. Steps in writing net ionic equations:

220. 1. Write the complete molecular equation
1. Write the complete molecular equation. (This is the type of equation that you are accustomed to writing.)

221. 2. Write the complete ionic equation
2. Write the complete ionic equation. To do this, you must ionize everything that is soluble and ionized in solution. Everything else is left together. Do not ionize solids, gases or weak electrolytes.

222. 3. Write the net ionic equation
3. Write the net ionic equation. To do this, cancel out all ions that are not participating in the reaction (spectator ions) and rewrite the equation.

223. Sodium chloride + silver nitrate
1. NaCl(aq) + AgNO3(aq) 
NaNO3(aq) + AgCl(s)
2. Na+ + Cl- + Ag+ + NO3- 
Na+ + NO3- + AgCl(s)
3. Cl- + Ag+ AgCl

224. Ex. HCl + Ba(OH)2  1. 2HCl + Ba(OH)2  2H2O + BaCl2
3. 2H+ + 2OH-  2H2O
H+ + OH-  H2O

225. Write net ionic equations for the following reactions:

226. 1. KCl(aq) + Pb(NO3)2(aq) 2KCl(aq) + Pb(NO3)2(aq)
2KNO3(aq) + PbCl2(s)
2K+ + 2Cl- + Pb2+ + 2NO3- 
2K+ + 2NO3- + PbCl2
Pb2+ + 2Cl-  PbCl2

227. 2. HCl(aq) + CaSO3(s) 2HCl(aq) + CaSO3(s)
H2O(l) + SO2(g) + CaCl2(aq)
2H+ + 2Cl- + CaSO3 
H2O + SO2 + Ca2+ + 2Cl-
2H+ + CaSO3 
H2O + SO2 + Ca2+

228. 3. Zn(s) + O2(g) 
2Zn(s) + O2(g) 2ZnO(s)

229. 4. Li(s) + H2O(l)  2Li(s) + 2H2O(l)  2LiOH(aq) + H2(g)

230. 5. Na2SO4(aq) + BaBr2(aq) Na2SO4(aq) + BaBr2(aq)
2NaBr(aq) + BaSO4(s)
2Na+ + SO42- + Ba2+ + 2Br- 
2Na+ + 2Br- + BaSO4
SO42- + Ba2+  BaSO4

231. 6. MgCO3(s)
MgCO3(s) MgO(s) + CO2(g)

232. 7. AgNO3(aq) + Na2CO3(aq)  2AgNO3(aq) + Na2CO3(aq) 
Ag2CO3(s) + 2NaNO3(aq)
2Ag+ + 2NO3- + 2Na+ + CO32- 
Ag2CO3 + 2Na+ + 2NO3-
2Ag+ + CO32-  Ag2CO3

233. 8. Na2S(aq) + HCl(aq)  Na2S(aq) + 2HCl(aq)  2NaCl(aq) + H2S(g)
2Na+ + S2- + 2H+ + 2Cl- 
2Na+ + 2Cl- + H2S
S2- + 2H+  H2S

234. 9. H2SO3(aq) 
H2SO3(aq) H2O(l) + SO2(g)

235. 10. Cl2(g) + NaI(aq) 
Cl2(g) + 2NaI(aq) I2(s) + 2NaCl(aq)
Cl2 + 2Na+ + 2I- I2 + 2Na+ + 2Cl-
Cl2 + 2I- I2 + 2Cl-

236. EXTRA EQUATION WORKSHEET PRE-AP CHEMISTRY

237. Complete the word equation, write the formula equation, balance it and identify the type of reaction. You many abbreviate as S, D, SR, DR, and C.

238. 1. heating magnesium carbonate
magnesium oxide + carbon dioxide
MgCO3  MgO + CO2
Decomposition

239. 2. complete combustion of propanol (C3H7OH)
propanol + oxygen 
carbon dioxide + water
2C3H7OH + 9O2  6CO2 + 8H2O
Combustion

240. S + O2  SO2 Synthesis 3. sulfur + oxygen 
sulfur + oxygen sulfur dioxide
S + O2  SO2
Synthesis

241. 4. sulfuric acid + cadmium 
cadmium sulfate + hydrogen
H2SO4 + Cd  CdSO4 + H2
Single Replacement

242. 5. sulfur dioxide + water 
sulfurous acid
SO2 + H2O  H2SO3
Synthesis

243. 6. hydrochloric acid(aq) + calcium carbonate(s) 
carbon dioxide(g) + water(l) + calcium chloride(aq)
2HCl + CaCO3  CO2 + H2O + CaCl2
Double replacement

244. 7. net ionic equation for #6
1. 2HCl(aq) + CaCO3(s) 
CO2(g) + H2O(l) + CaCl2(aq)
2. 2H+ + 2Cl- + CaCO3 
CO2 + H2O + Ca2+ + 2Cl-
3. 2H+ + CaCO3 
CO2 + H2O + Ca2+

245. 8. silver nitrate (aq)+ hydrochloric acid (aq)
silver chloride(s) + nitric acid(aq)
AgNO3 + HCl  AgCl + HNO3
Double replacement

246. 9. net ionic equation for #8
1. AgNO3(aq) + HCl(aq) 
AgCl(s) + HNO3(aq)
2. Ag+ + NO3- + H+ + Cl- 
AgCl(s) + H+ + NO3-
3. Ag+ + Cl-  AgCl(s)

247. 10. barium nitrate(aq) + potassium sulfate (aq)
barium sulfate(s) + potassium nitrate(aq)
Ba(NO3)2 + K2SO4  BaSO4 + 2KNO3
Double Replacement

248. 11. net ionic equation for #10
1. Ba(NO3)2 (aq) + K2SO4(aq)  BaSO4(s) + 2KNO3(aq)
2. Ba2+ + 2NO3- + 2K+ + SO42- 
BaSO4 + 2K+ + 2NO3-
3. Ba2+ + SO42-  BaSO4

249. 12. sodium hydroxide + phosphoric acid 
sodium phosphate + water
3NaOH + H3PO4  Na3PO4 + 3H2O
Double replacement

250. 13. iodine + rubidium chloride 
iodine + rubidium chloride  No Rxn

251. 14. magnesium(s) + copper(II) sulfate(aq)
magnesium sulfate(aq) + copper(s)
Mg + CuSO4  MgSO4 + Cu
Single replacement

252. 15. net ionic equation for #14
1. Mg(s) + CuSO4(aq)  MgSO4(aq) + Cu(s)
2. Mg + Cu2+ + SO42- 
Mg2+ +SO42- + Cu
3. Mg + Cu2+  Mg2+ + Cu

253. 16. ammonium nitrate(aq) + sodium hydroxide(aq) 
ammonium nitrate(aq) + sodium hydroxide(aq)  ammonia (g)+ water (l) + sodium nitrate (aq)
NH4NO3 + NaOH 
NH3 + H2O + NaNO3
Double replacement

254. 17. net ionic equation for #16
1. NH4NO3(aq) + NaOH(aq) 
NH3(g) + H2O(l) + NaNO3(aq)
2. NH4+ + NO3- + Na+ + OH- 
NH3 + H2O + Na+ + NO3-
3. NH4+ + OH-  NH3 + H2O

255. 18. potassium(s) + water(l) 
potassium hydroxide(aq) + hydrogen(g)
2K + 2H2O  2KOH + H2
Single Replacement

256. 19. net ionic equation for #18
1. 2K(s) + 2H2O(l) 
2KOH(aq) + H2(g)
2. 2K + 2H2O  2K+ + 2OH- + H2

257. 20. sodium bromide(aq) + chlorine(g)
sodium chloride + bromine
2NaBr + Cl2  2NaCl + Br2
Single replacement

258. 21. net ionic equation for #20
1. 2NaBr(aq) + Cl2(g)  2NaCl(aq) + Br2(l)
2. 2Na+ + 2Br- + Cl2 
2Na+ + 2Cl- + Br2
3. 2Br- + Cl2  2Cl- + Br2

259. aluminum + nitrogen aluminum nitride 2Al + N2  2AlN Synthesis

260. 23. sodium sulfide(aq) + hydrochloric acid(aq)
sodium sulfide(aq) + hydrochloric acid(aq) sodium chloride (aq) + hydrogen sulfide (g)
Na2S + 2HCl  2NaCl + H2S
Double replacement

261. 24. net ionic equation for #23
1. Na2S(aq) + 2HCl(aq)  2NaCl(aq) + H2S(g)
2. 2Na+ + S2-+ 2H+ + 2Cl- 
2Na+ + 2Cl-+ H2S
3. S2-+ 2H+  H2S

262. 25. heating magnesium sulfate heptahydrate
magnesium sulfate + water
MgSO4.7H2O  MgSO4 + 7H2O
Decomposition

263. 26. heating mercury(II) oxide
mercury + oxygen
2HgO  2Hg + O2
Decomposition

264. 27. bromine + strontium chloride
bromine + strontium chloride No Rxn

265. 1. Dilute hydrochloric acid is added to a solution of potassium sulfite.
2HCl(aq) +K2SO3(aq) H2O(l) + SO2(g) +2KCl(aq)
2H+ + 2Cl- +2K+ + SO32-
H2O(l) + SO2(g) +2K+ +2Cl-
2H+ + SO32- H2O(l) + SO2(g)

266. 2. A solution of sodium sulfide is added to a solution of zinc nitrate.
Na2S(aq) + Zn(NO3)2(aq)  2NaNO3(aq) + ZnS(s)
2Na+ + S2- + Zn2+ + 2NO3-  2Na+ + 2NO3- + ZnS
S2- + Zn2+  ZnS

267. 3. Chlorine gas is bubbled into a solution of potassium iodide.
Cl2(g) + 2KI(aq)  2KCl(aq) + I2(s)
Cl2 + 2K+ + 2I-  2K+ + 2Cl- + I2
Cl2 + 2I- -> 2Cl- + I2

268. 4. Magnesium metal is burned in nitrogen gas.
3Mg(s) + N2(g)  Mg3N2(s)

269. 5. Solid sodium oxide is added to water.
Na2O(s) + H2O(l)  2NaOH(aq)
Na2O(s) + H2O(l) 2Na+(aq) + 2OH-(aq)