Unit 6 Review The Mole
1. Which of the following sets of empirical formula, molar mass, and molecular formula is correct A. CH, 78 g, C13H13 B. CH4N, 90 g, C3H12N3 C. C2H3O, 55 g, C2H6O7 D. NO3, 127 g, N3O9
A. kilogram B. mole C. liter D. Kelvin 2. What SI unit is used to measure the number of representative particles in a substance? A. kilogram B. mole C. liter D. Kelvin
A. gold B. iron C. chlorine D. silicon 3. A 22.4 L sample of which of the following substances, at STP, would contain 6.02 x 1023 representative particles A. gold B. iron C. chlorine D. silicon
0o C and 1 atm B. 100o C and 1 atm C. 0 K and 0 atm D. 0 K and 1 atm 4. Which combination of temperature and pressure correctly describes standard temperature and pressure, STP? 0o C and 1 atm B. 100o C and 1 atm C. 0 K and 0 atm D. 0 K and 1 atm
5. Avogadro’s number of representative particles is equal to one ____. A. Furry animal B. STP C. liter D. mole
6. How many moles of Mn are 3.0 x 1023 Mn atoms? A. 5.0 moles B. 54.94 moles C. 1.0 moles D. 0.50 moles
7. How many moles are in 16.0 g of SO2? A. 4.0 mol B. 64.0 mol C. 0.25 mol D. 0.16 mol
8. The molar volume of any gas at STP occupies ____. A. 1 L B. 22.4 L C. 1 atm D. 22.4 atm
A. Empirical formula B. Molecular formula C. Mole formula 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
10. How many hydrogen atoms are in 5 molecules of isopropyl alcohol, C3H7O? B. 5 C. 7 D. 35
11. Which of the following compounds have the same empirical formula A. C7H14 and C10H20 B. C6H12 and C6H14 C. CH3 and C3H12 D. N2O4 and N2O10
12. What is the molar mass of nitrogen gas? A. 14.01 g/mol B. 28.02 g/mol C. 14.01 amu D. 28.02 amu
A. solids B. liquids C. gases D. matter 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
14. Which of the following is NOT an empirical formula A. CH4 B. NO C. C2H2O4 D. CHO
The masses of the individual elements and the mass of the compound. 15. What information is needed to calculate the percent composition of a compound? 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. The volume of the sample and the masses of the individual elements.
A. atoms B. molecules C. formula units D. acids 16. CuCl is made up of which of the following representative particles? A. atoms B. molecules C. formula units D. acids
17. How many potassium ions are present in 2.00 mol of K2O? A. 6.02 x 1023 B. 3.01 x 1023 C. 2.41 x 1024 D. 1.20 x 1024
18. 15 molecules of CO2 have a molecular mass of 44.01 amu 44.01 g 660 g 660 amu
19. What is the molecular mass of SiO2? 28.09 amu 32.00 amu 72.18 amu 60.09 amu
20. The percent composition of CH4 is 80 % C and 20 % H 20 % C and 80 % H 75 % C and 25 % H 25 % C and 75 % H
Answers 1. B 9. A 17. C 2. B 10. D 18. D 3. C 11. A 19. D 4. A 12. B 20. C 5. D 13. C 6. D 14. C 7. C 15. A 8. B 16. C