What was the original concentration of the naoh solution -

Question

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