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1. 6.02x1023 is....
a random number Avogadro's number stoichiometry percent yield None of these

2. 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%

3. What is the mass percent of oxygen in H2SO4 (sulfuric acid)?
0 1% 2.04% 32.70% 65.26%

4. 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

5. 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

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

7. 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

8. 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

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

10. How many kilometers are in 10.00 miles? (1 inch equals exactly 2.54 centimeters)
2.04 km 4.09 km 8.09 km 16.09 km None of these

11. When aluminum reacts with sulfuric acid, the result is aluminum sulfate and hydrogen gas. How many moles of sulfuric acid (H2SO4) will react with 24 moles of aluminum?
12 14 16 18 20

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

13. 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

14. The formation of ammonia is shown by the following reaction: N2 (g) + 3H2 (g)--> 2NH3 (g). You are given 13.85 grams of nitrogen and 5.27 grams of hydrogen. If the experiment produced 3.297 grams of ammonia, then what is the percent yield?
25% 50% 35.80% 76.60% None of these

15. 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

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