1. Midterm Reaction Review
Answers

2. DIRECTIONS:
Write net ionic equations for the following reactions.
For extra practice, classify and balance each reaction.

3. 1. Solid zinc carbonate is added to 1.0 M sulfuric acid.
ZnCO3(s) + 2 H+(aq)  Zn(s) + CO2(g) + H2O(l)
metathesis

4. 2. A 0.02 M hydrochloric acid solution is mixed with an equal volume of a 0.01 M calcium hydroxide solution.
(OH)- (aq) + H+ (aq)  H2O(l)
Metathesis (acid base)

5. 3. Magnesium ribbon is burned in oxygen.
2 Mg(s) + O2(g)  2 MgO(s)
Combination/synthesis

6. 4. Solid sodium carbonate is heated strongly
Na2CO3(s)  Na2O(s) + CO2(g)
decomposition

7. 5. A bar of strontium metal is immersed in a 1
5. A bar of strontium metal is immersed in a 1.0 M copper (II) nitrate solution.
Sr(s) + Cu+2 (aq)  Sr+2 (aq) + Cu(s)
Single replacement

8. 6. Methane is burned in air.
CH4(g) + O2(g)  CO2(g) + 2 H2O(l)
combustion

9. 7. A solution of lead (II) nitrate is added to a solution of potassium sulfate.
Pb+2 (aq) + (SO4)-2 (aq)  PbSO4(s)
Metathesis

10. 8. A strip of magnesium metal is placed in 1.0M hydrochloric acid.
Mg(s) + 2 H+ (aq)  Mg+2 (aq) + H2(g)
Single replacement

11. 9. Sulfur trioxide gas is bubbled into water.
Eq: SO3(g) + H2O(l)  H2SO4(aq)
SO3(g) + H2O(l)  2H+ (aq) + (SO4)-2 (aq)
Combination/synthesis

12. 10. Excess concentrated potassium hydroxide solution is added to a solution of nickel (II) chloride.
Ni+2 (aq) + (OH)- (aq)  Ni(OH)2(s)
metathesis

13. 11. Sulfur dioxide gas is bubbled into distilled water.
Eq: SO2(g) + H2O(l)  H2SO3(aq)
SO2(g) + H2O(l)  2 H+ (aq) + SO3-2 (aq)
Combination/synthesis

14. 12. A piece of copper wire is placed in a solution of silver nitrate.
Cu(s) + Ag+ (aq)  Cu+2 (aq) + Ag(l)
Single replacement

15. 13. Solutions of strontium nitrate and sodium sulfate are mixed
Sr+2 (aq) + (SO4)-2 (aq)  SrSO4(s)
metathesis

16. 14. Powdered magnesium carbonate is heated strongly.
MgCO3(s)  MgO(s) + CO2(g)
Decomposition

17. 15. A small piece of calcium metal is added to hot distilled water.
Ca(s) + H2O(l)  Ca+2 (aq) + (OH)- (aq) + H2(g)
Single replacement

18. 16. Lithium metal is strongly heated in nitrogen gas.
6Li(s) + N2(g)  2 Li3N(s)
Combination/synthesis

19. 17. A solution of copper (II) chloride is added to a solution of sodium sulfide.
Cu+2 (aq) + S-2 (aq)  CuS(s)
Metathesis

20. 18. A solution of potassium carbonate is added to a solution of strontium chloride.
Sr+2(aq) + (CO3)-2(aq)  SrCO3(s)
Metathesis

21. 19. Solid lead (II) carbonate is added to a 0
19. Solid lead (II) carbonate is added to a 0.5 M sulfuric acid solution.
PbCO3 + H+ (aq)  Pb+2 (aq) + CO2(g) + H2O(l)
Metathesis

22. 20. A mixture of powdered iron (III) oxide and aluminum metal is heated strongly.
Fe2O3(s) + Al(s)  Al2O3(s) + Fe(s)
Single replacement

23. 21. A 0. 2 M barium nitrate solution is added to an alkaline 0
21. A 0.2 M barium nitrate solution is added to an alkaline 0.2 M potassium chromate solution.
Ba+2(aq) + (CrO4)-2(aq)  BaCrO4(s)
Metathesis

24. 22. Solutions of cobalt (II) nitrate and sodium hydroxide are mixed.
Co+2 (aq) + 2 (OH)- (aq)  Co(OH)2(s)
Metathesis

25. 23. Ethane gas is burned in air.
2 C2H6(g) + 7 O2(g)  4 CO2(g) + 6 H2O(l)
combustion

26. 24. A strip of zinc is added to a solution of 6
24. A strip of zinc is added to a solution of 6.0-molar hydrobromic acid.
Zn(s) + 2 H+(aq)  Zn+2 (aq) + H2(g)
Single replacement

27. 25. Excess potassium hydroxide solution is added to a solution of aluminum nitrate.
Al+3 (aq) + 3 (OH)- (aq)  Al(OH)3(s)
Metathesis

28. 26. A strip of magnesium metal is heated strongly in pure nitrogen gas.
3 Mg(s) + N2(g)  Mg3N2(s)
Combination/synthesis

29. 27. A solution of nickel chloride is added to a solution of sodium sulfide.
Ni+2 (aq) + S-2 (aq)  NiS(s)
Metathesis

30. 28. A strip of lead metal is added to a solution of silver nitrate.
Pb(s) + Ag+ (aq)  Pb+2 (aq) + Ag(s)
Single replacement

31. 29. Solid calcium carbonate is strongly heated.
CaCO3(s)  CaO(s) + CO2(g)
decomposition

32. 30. A piece of nickel metal is immersed in a solution of copper (II) sulfate.
Ni(s) + Cu+2 (aq)  Ni+2 (aq) + Cu(s)
Single replacement

33. 31. A small piece of potassium is added to water.
K(s) + 2 H2O(l)  K+ (aq) + 2 (OH)- (aq) + H2(g)
Single replacement

34. 32. Propane is burned in oxygen.
C3H8(g) + 5 O2(g)  3 CO2(g) + 4 H2O(l)
combustion

35. 33. Solid barium oxide is added to distilled water.
BaO(s) + H2O(l)  Ba+2 (aq) + 2 (OH)- (aq)
metathesis

36. 34. Hydrogen sulfide gas is bubbled into a solution of mercury (II) chloride.
H2S(g) + Hg+2 (aq)  HgS(s) + 2 H+ (aq)
metathesis

37. 35. A bar of zinc metal is immersed in a solution of copper (II) sulfate.
Zn(s) + Cu+2 (aq)  Zn+2 (aq) + Cu(s)
Single replacement

38. 36. Solutions of manganese (II) sulfate and ammonium sulfide are mixed.
Mn+2 (aq) + S-2 (aq)  MnS (s)
Metathesis

39. 37. Carbon dioxide gas is bubbled through a concentrated solution of potassium hydroxide.
Eq: KOH(aq) + CO2(g) ---> KHCO3(aq)
CO2 (g) + (OH)- (aq)  (HCO3)- (aq)

40. 38. A small piece of sodium metal is added to distilled water.
2Na (s) + 2H2O(l)  2Na+ (aq) + 2(OH)- (aq) + H2 (g)
Single replacement

41. 39. Equal volumes of 0.1M solutions of lead (II) nitrate and magnesium iodide are combined.
Pb+2 (aq) + 2 I- (aq)  PbI2 (s)
metathesis

42. 40. An excess of sodium hydroxide solution is added to a solution of magnesium nitrate.
2 (OH)- (aq) + Mg+2 (aq)  Mg(OH)2 (s)
metathesis

43. 41. A piece of aluminum metal is added to a solution of silver nitrate.
Al(s) + Ag+(aq)  Al+3(aq) + Ag(s)
Single replacement