1. Unit 5 Review The Mole

2. 1. What is the mass of 1 mole of iron atoms? A. 55.85 amu B. 55.85 L C. 55.85 x 10 23 D. 55.85 g

3. 2. What SI unit is used to measure the number of representative particles in a substance? A. kilogram B. mole C. liter D. Kelvin

4. 3. What is the mass % of H in CH 4 ? A. 100 % B. 50 % C. 25 % D. 4 %

5. 4. Which combination of temperature and pressure correctly describes standard temperature and pressure, STP? A.0 o C and 1 atm B. 100 o C and 1 atm C. 0 K and 0 atm D. O K and 1 atm

6. 5. Avogadro’s number of representative particles is equal to one ____. A. Furry animal B. STP C. liter D. mole

7. 6. How many moles of Mn are 3.01 x 10 23 Mn atoms? A. 5.0 moles B. 54.94 moles C. 1.0 moles D. 0.50 moles

8. 7. What is the molar mass of KCl? A. 74.55 g/mol B. 39.10 g/mol C. 35.45 g/mol D. 96.87 g/mol

9. 8. The molar volume of any gas at STP occupies ____. A. 1 L B. 22.4 L C. 1 atm D. 22.4 atm

10. 9. The lowest whole-number ratio of the elements in a compound is called the ____. A. Empirical formula B. Molecular formula C. Mole formula D. None of the above

11. 10. How many hydrogen atoms are in 5 molecules of isopropyl alcohol, C 3 H 7 O? A. 15 B. 5 C. 7 D. 35

12. 11. Which of the following compounds have the same empirical formula A. CH 2 and C 7 H 14 B. C 6 H 12 and C 6 H 14 C.CH 3 and C 3 H 8 D. N 2 O 4 and N 2 O 10

13. 12. What is the molar mass of nitrogen gas? A. 14.01 g B. 28.02 g C. 14.01 amu D. 28.02 amu

14. 13. The volume of one mole of a substance is 22.4 L at STP for all ____. A. solids B. liquids C. gases D. matter

15. 14. Which of the following is NOT an empirical formula A. CH 4 B. NO C. C 2 H 2 O 4 D. CHO

16. 15. What information is needed to calculate the percent composition of a compound? A.The masses of the individual elements and the mass of the compound. B. The formula of the compound and the density. C. The mass of the compound and the density. D.The volume of the sample and the masses of the individual elements.

17. 16. The empirical formula of a compound is CH 3 and the molar mass of the compound is 30 g/mol. What is the molecular formula? A. CH 3 B. C 10 H 10 C. C 2 H 6 D. C 6 H 2

18. 17. How many potassium ions are present in 2.00 mol of K 2 O? A. 6.02 x 10 23 B. 3.01 x 10 23 C. 2.41 x 10 24 D. 1.20 x 10 24

19. 18. 15 molecules of CO 2 have a molecular mass of A.44.01 amu B.44.01 g C.660 g D.660 amu

20. Answers 1.D9. A17. C 2.B10. D18. D 3.C11. A 4.A12. B 5.D13. C 6.D14. C 7.A15. A 8.B16. C