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Name: _____________________________________________
Period: ____
CHEMISTRY FINAL EXAM REVIEW 2012
Chemical Reactions
1. For a chemical equation to support the law of conservation of mass it must be ___________________.
2. Balance the following equations:
a. __NH3 (g) + __ O2 (g)  __ N2 (g) + __ H2O (g)
b. __N2H4 + __N2O4  __N2 + __H2O
c. __CH3CH2OH + __O2  __CO2 + __H2O
d. __H2 + __Br2  __HBr
e. __AlCl3 (aq) + __Ba(OH)2 (aq)  __Al(OH)3 (s) + __BaCl2 (aq)
f.
__CH4 + __Cl2  __CH2Cl2 + __HCl
g. __H2O + __MgO  __Mg(OH)2
3. Zn + CuSO4  Cu + ZnSO4 Is an example of a _____________________________________ reaction.
4. NaF + HCl  HF + NaCl Is an example of a _____________________________________ reaction.
5. 2 NaCl  2 Na + Cl2 Is an example of a _____________________________________ reaction.
Stoichiometry
6. Photosynthesis: 6CO2 + 6H2O  C6H12O6 + 6O2 To produce 4 molecules of sugar, a plant needs how
many molecules of water?
7. When 127 g of copper reacts with 32 g of oxygen gas to form copper (II) oxide, no copper or oxygen is left
over. How much copper (II) oxide is produced? 2Cu + O2  2CuO
8. A mass of 5.4 grams of aluminum (Al) reacts with an excess of copper (II) chloride (CuCl2) in solution. What
mass of solid copper (Cu) is produced? 3 CuCl2 + 2 Al  2 AlCl3 + 3 Cu
9. In this reaction, Fe2O3 + 3CO  2 Fe + 3 CO2, how many grams of Fe2O3 are required to completely
react with 84 grams of CO?
10. Carbon disulfide is prepared industrially by reacting carbon with sulfur dioxide according to the above
equation. If 5.9 moles of carbon react, how many moles of CS2 are produced? 5 C + 2 SO2  CS2 + 4 CO
11. When copper reacts with silver nitrate according to the equation, Cu (s) + 2 AgNO3 (aq)  Cu(NO3)2 (aq)
+ 2 Ag (s), what is the number of grams of copper required to produce 432 grams of silver?
12. If 54.0 grams of water are mixed with excess magnesium nitride, then how many grams of ammonia are
produced? Mg3N2 (s) + 6 H2O (l)  2 NH3 (aq) + 3 Mg(OH)2 (s)
Gases
13. When a cold tire is inflated to a certain pressure and then is warmed up due to the friction with the road, the
pressure increases. Why?
14. The molar volume of an ideal gas in liters at STP is ___________________.
15. What are the values of standard temperature and pressure?
16. A tank contains N2 at 1.0 atm and O2 at 2.0 atm. Helium is added to this tank until the total pressure is 6.0
atm. What is the partial pressure of the helium?
17. What is the equivalent of 423 kelvin in degrees Celsius?
18. A sample of carbon dioxide gas occupies a volume of 20 L at standard temperature and pressure (STP).
What will be the volume of a sample of argon gas that has the same number of moles and pressure but
twice the absolute temperature?
19. A gas cylinder with a volume of 3.00 dm3 contains 8.00 moles of oxygen gas at a temperature of 50.0 K.
What is the pressure inside the cylinder? (R = 8.31 kPa·dm3/moles·K)
20. The volume of 400 mL of chlorine gas at 400 mmHg is decreased to 200 mL at constant temperature. What
is the new gas pressure?
21. How many liters of oxygen are required to produce 2 liters of water at STP? 2 H2 (g) + O2 (g)  2 H2O (g)
Acids and Bases
22. When HCl reacts with NaOH in a neutralization reaction, what two products are formed?
23. What are the observable properties of most acids?
24. What are the observable properties of most bases?
25. According to Arrhenius, a base is a substance that _________________________________________.
26. According to Brønsted-Lowry, an acid is a substance that ___________________________________.
27. Equal volumes of 1 molar hydrochloric acid (HCl) and 1 molar sodium hydroxide (NaOH) are mixed. After
mixing, the solution will be approximately what pH?
28. What is the process of determining the concentration of an unknown solution by using a known solution?
29. Identify the following reactions as neutralization, redox or precepitiation reactions.
a. NO2 (g)+ H2O (l)  HNO3 (aq)+ NO (g)
b. 2 KOH (aq) + H2SO4 (aq) ---> K2SO4 (aq) + 2 H2O (l)
c. AgNO3 (aq) + KCl (aq) ----> AgCl (s) + KNO3 (aq)
d. Ca(OH)2 (aq) + 2 HCl (aq)
e.
f.
CaCl2 (aq) + 2 H2O (aq)
H2S (aq) + HNO3 (aq)  S (s) + NO (g) + H2O (l)
Ca3(PO4)2 (aq) + 3 H2SO4 (aq)
3 CaSO4 (s) + 2 H3PO4 (aq)
Solutions
30. Water has several unique properties such as high boiling point, high surface tension and low vapor pressure.
What are the main causes for these properties?
31. What happens at the triple point on a phase diagram?
32. Like dissolves like refers to the molecule’s _________________________.
33. What type of change is the process of dissolving?
34. A teaspoon of dry coffee crystals dissolves when mixed in a cup of hot water. This process produces a coffee
solution. The crystals are classified as the ____________________________.
35. A technician prepared a solution by heating 100 milliliters of distilled water while adding KCl crystals until no
more KCl would dissolve. She then capped the clear solution and set it aside on the lab bench. After several
hours she noticed the solution had become cloudy and some solid had settled to the bottom of the flask.
What happened?
36. The universal solvent is _________________________.
37. What are the three factors that affect solubility?
38. If the amount of solute present in a solution at a given temperature is less than the maximum amount that
can dissolve at that temperature, the solution is said to be ____________________________.
39. As temperature increases, solubility of gases _____________________________.
40. Why is a molecule of hydrogen chloride polar?
41. What type of solution will prodice crystals if disturbed?
42. To conduct electricity, a solution must contain ________________________________.
43. What is the final concentration if 50.0 mL of a 2.00 M solution are diluted to 500.0 mL?
44. How many moles of HCl are present in 0.70 L of a 0.33 M HCl solution?
45. How many moles of HNO3 are needed to prepare 5.0 liters of a 2.0 M solution of HNO3?
Thermochemistry
46. Give two examples of an exothermic reaction.
47. Give two examples of an endothermic reaction.
48. The energy transferred between samples of matter because of a difference in their temperatures is _______.
49. The specific heat of copper is about 0.4 joules/grams∙°C. How much heat is needed to change the
temperature of a 30-gram sample of copper from 20.0°C to 60.0°C?
50. If the heat of fusion is 32.2 kJ/mol, how much heat energy is required to melt 5.67 grams of FeO?