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1. On a faraway planet, the following system of measurement is used: 1 zorg = 5.81 zaks 1 zak = .87 zips 1 zip = 2.52 zeeks 1 zeek = 10.02 yaks 1 yak = 3.91 zaps How many zorgs are in 3.20 zaps?
5.81 12.53 2.74 0.00641 None of these

2. A chemistry student was performing an experiment involving the following reaction: C3H8 (g) + O2 (g) --> CO2 (g) + H2O (g), balancing it with the coefficients 1, 5, 2, and 4 respectively. The oxygen was in excess. He used 20.18 grams of C3H8. When he measured the amount of CO2 produced, he was astounded to find that 46.22 grams were produced, 5.88 grams more than the theoretical yield of 40.34. What went wrong? Hint: Look at the formula
C3H8's coefficient should be 3, not 1 CO2's coefficient should be 3, not 2 O2's coefficient should be 3, not 5 Water's coefficient should be 3, not 4 None of these

3. When 2 moles of propane (C3H8, MW = 44 grams) is combusted with oxygen gas, how many grams of CO2 (MW: 44 grams) are produced?
88 44 3 132 264

4. How many carbon molecules are present in 5.0 grams of glucose? (C6H12O6)
1.0 * 10^22 5.1 * 10^22 1.0 * 10^23 6 None

5. If 11 grams in a reaction was obtained, and you had a theoretical yield of 14 grams, what is your % yield?
0.79% 79% 11% 14% 12%

6. How many moles in 20 g of water?
1.11 20 18 1.1 42

7. 6.02x1023 is....
a random number Avogadro's number stoichiometry percent yield None of these

8. How many grams is 0.25 moles of table salt (NaCl?)
58.44 grams 14.61 grams 14.6 grams 58 grams 15 grams

9. Hydrogen gas and oxygen gas can form water. What mass of water will form from excess oxygen and 24.0 g H2? (Assume a complete reaction)
107 216 24.0 48.0 96.0

10. Hydrochloric acid reacts with calcium carbonate yielding calcium chloride, water, and carbon dioxide. How many moles of calcium carbonate would be necessary to react with 8 moles of HCl?
1 2 3 4 5

11. Balance the following equation (find what number coefficient X is): NH3 (g) + O2 (g) --> NO (g) + XH2O (g).
2 3 4 5 6

12. Substance A combines with substance B to form Substance AB. B is a diatomic molecule. You are given 3.15 moles of B2. If A is in excess, how many moles of AB are produced?
1.20 2.30 3.25 5.60 6.30

13. The combustion of butane (C4H10 with oxygen gas will yield carbon dioxide and water. Calculate the % yield of CO2 when 42 grams of butane are burned with 16.0 grams of oxygen and 10. grams of CO2 was formed.
25% 100% 32% 74% 64%

14. What is the % mass of carbon in carbon dioxide?
44% 25% 27% 63% 50%

15. Ferric chloride can be made by the reaction of iron with chlorine gas. How much mass, in grams, is needed to completely react with 24.0 g chlorine gas?
12.59 24.0 48.0 12.6 48.01

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