Concentration Calculations
1L = 1000mL
Molarity
1. If water is added to 2.00 mol of glucose to give 5.00L of solution, what is the
concentration?
2. How many moles of solute are in 250 mL of a 2.00 mol/L CaCl2 solution? (HINT: convert
mL to L first!)
3. How many litres of water are needed to make a 5.00 M solution that has 15.0 mol of NaCl
in it?
4. Determine the concentration of a solution containing 10.0 g of calcium chloride (CaCl2) in
645.0 mL of solution. (1 mol= ? g [molar mass])
5. Calculate the mass (g) of solute required to prepare 4.20 L of a 0.100 mol/L solution of
hydrochloric acid (HCl). (1 mol= ? g [molar mass])
6. How many litres of 1.5 mol/L solution can be prepared from 388.4 g of K2CrO4? (1 mol= ?
g [molar mass])
Parts Per Million (ppm) and Parts Per Billion (ppb) Calculations
NOTE:
Use the following conversion factors to convert all of your numbers to grams before
entering them into your formulas.
1 g = 1000 mg
1 kg = 1000 g
7. What is the concentration in ppm of selenium if 1.3 milligrams is found in 2500kg of soil?
8. Calculate the mass of solvent in a 6 ppm solution of a drug if the mass of the solute is
5.0 x 10-5 g.
9. Calculate the mass of solute PCB’s in a 65 kg person if the concentration is 4 ppm?
10. What is the concentration in ppb of PCB’s in a chemical spill if there is 6.0 x 10-5 g in
4.6 x 106 g of soil?
Dilution Calculations
M1V1 = M2V2
Please show what you are solving for and round all answers to the correct sig. figs. Include units
throughout your work, not just the answer.
11. What volume of your stock solution would you need to prepare 250 mL of 0.10 mol/L HCl
from 12.0 mol/L HCl?
12. If 10.0 mL of a 0.560 M solution of aluminum nitrate is diluted to 250.0 mL, what is the
concentration of aluminum nitrate in the new solution?
13. Calculate the concentration of the solution formed if a 250.0 mL sample of 10.0 mol/L
nitric acid (HNO3) is placed in a 500.0 mL volumetric flask and the flask is filled to the
mark with distilled water.
14. What is the total volume of 3.0 mol/L sulfuric acid (H2SO4) that can be prepared from a
5.0 L solution of 18.0 mol/L sulfuric acid?
15. A stock solution of 1.00M NaCl is available. What volume (mL) is needed to make 100.0mL
of a 0.750M solution?
Serial Dilution
16. You want to create a series of solutions by diluting a stock solution of 10 mol/L HCl (aq).
You will transfer 10.0 mL into each new container and make up the volume to 50.0mL.
Calculate the concentrations of the first 3 serial dilutions.