Dilution quiz

The initial concentration of a 10 mL solution was 27 mg/mL. The solution was diluted by a factor of 3. What is the final concentration?

• 81 mg/mL

• 9 mg/mL

• 10 mL

• 2.7 mg/mL

20 mL of a 0.200 M working solution was made from a concentrated stock using a dilution factor of 25. What was the concentration of the concentrated stock?

• 5 M

• .008 M

• 125 M