Mixed Moles Practice
1. What mass of silicon dioxide contains 9.72x1024 atoms of oxygen?
2. Mrs. Atkins has a stock solution of 4.50M barium hydroxide. She needs a solution with
[Ba(OH)2]=1.75M for a lab. How many mL of the stock solution will she need to make
2.5L of solution for the lab?
3. How many mL of a 2.54M copper(II) nitrate solution are required to obtain 8.50x1023
oxygen atoms?
4. A typical cup of coffee contains 100.0mg caffeine (C8H10N4O2). How many atoms of
nitrogen are contained in a typical cup of coffee?
5. A sample of 2.72M lithium sulfide is found to contain 8.14x1022 lithium ions. What is
the volume in mL of the sample?
6. What is the concentration of 750mL of solution containing 127 g of ammonium sulfate?
7. How many oxygen atoms are contained in a 42.3g sample of sodium nitrite?
8. A sample of chromium(III) oxide contains 9.74x1024 chromium ions. What is the mass
of this sample in kg?
9. How many atoms of oxygen are found in a 45.0mL sample of 1.82M calcium phosphate?
10. A supervisor in an electroplating operation needs a solution of 0.23M nickel(II) chloride for a process. In
order to make 520L of solution, how much 3.0M nickel(II) chloride solution should she order?
11. How many chloride ions are contained in 84.2mL of 0.124M magnesium chloride
solution?
12. What mass of beryllium fluoride contains 3.14x1022 fluoride ions?
13. How many mL of 0.940M barium hydroxide are required to obtain 1.67x1023 hydrogen
atoms?
14. What mass of methane contains 3.00x1023 hydrogen atoms?
15. What mass of lithium carbonate is needed to make 140.0mL of a 0.049M solution?
16. How many hydrogen atoms are present in a 17.4g sample of ethanol, CH3OH?
17. 225mL of a solution of 1.20M barium nitrate is needed to use in a lab. If the available
stock solution is 3.00M, how much of that solution is needed?
18. Splenda or sucralose, C12H19Cl3O8, is packaged in 3.00g packets for sale. How many
chlorine atoms are contained in one packet of Splenda?
Mixed Moles Practice Answers
1. 485g SiO2
2. 970mL stock solution
3. 92.6mL Cu(NO3)2
4. 1.240x1021 atoms nitrogen
5. 24.8mL Li2S
6. 1.3M (NH4)2SO4
7. 7.38x1023 atoms oxygen
8. 1.23 kg Cr2O3
9. 3.95x1023 atoms oxygen
10. 4.0 x101 L NiCl2
11. 1.26x1022 ions chloride
12. 1.23g BeF2
13. 148mL Ba(OH)2
14. 2.00g CH4
15. 0.51g Li2CO3
16. 1.31x1024 atoms hydrogen
17. 0.0900L Ba(NO3)2
18. 1.36x1022 atoms chlorine