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Concentration Exercises Tasksheet #7
Name _____________________show all work! Fall 2013
1. I need 800 mL of a 13.0 % w/v solution of glucose. How many grams of glucose are present in this solution ?
2. I would like to make a aqueous solution using 240 mL of ethylene glycol as the solute. What would the final volume of the solution have to be to have a 40% v/v concentration?
3. The EPA just checked the concentration levels of SO2 in the atmosphere in our area, and found it to be 21 ppb. If I inhale 3,500. g of air per day, how many grams of sulfur dioxide are present in this air ?
4. I want a 1.50 M solution of KNO3 in water, and I need 250 mL of it. How many grams of KNO3
are needed to prepare this solution?
5. 76.0 g of AgNO3 are dissolved in 500mL of water. What is the %w/v of this solution? What is the
molarity ?
6. 25.0 mL of 18.0 M H2SO4 is transferred to a volumetric flask and filled to the 250 mL mark with
distilled water. What is the final molarity?
7. 175.0 mL of a MgSO4 solution was transferred to a 500 mL volumetric flask and diluted up to
the mark. If the final concentration is 1.25 M, what was the original concentration of first
solution?
8. I have a 1.20 M solution of Na2CO3. If I need 0.75 mol of Na2CO2 for an experiment, how many
mL of this solution will I need to use ?
NEW:
Acid/Base Exercises Tasksheet #8
Name _____________________show all work! CHM 131
1. The [H3O+] concentration in a solution is 3.4 x 10-4 M What is the pH ?
2. 2.50 g of HBr is dissolved in 2000 mL of pure water. What is the pH ?
3. The [OH-] of a base solution is 7.3 x 10-4 M. What is the [H3O+] ?
4. The [OH-] concentration of a basic solution is 2.5 x 10-2 M. What is the pH ?
5. 2.50 g of NaOH is dissolved in 2000 mL of pure water. What is the pH ?
6. A solution has a pH of 5.79 What is the [H3O+] ?
7. A solution has a pH of 10.45. What is the [OH-] ?
8. A 35.0 mL sample of HCl is placed in flask with a few drops of indicator, and titrated with
45.9 mL of a 0.15 M NaOH hydroxide solution, at which point the indicator changed color.
What was the original concentration of the HCl solution?
9. A 50.0 mL NaOH solution of unknown concentration is titrated with 34.7 mL of 0.20 M HCl. What
was the original concentration of the NaOH solution ?
10. A HF/NaF buffer system was set up with [HF] = 1.00 M, and [NaF] = 1.25 M. What is the pH of this
buffer?
Ka of HF = 7.2 x 10-4
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