imported_Devaki
New member
There are a few questions that I've been trying to find the answer to but to no avail ):
Please help!
1) What mass of sodium nitrite must be added to 250 mL of a 0.200 M nitrous acid solution to make a buffer with pH = 3.00?
a. 30.90 g
b. 1.54 g
c. 3.44 g
d. 1.07 g
2) (Points: 1)
How many mL of 4.50 M sodium hydroxide must be added to 250 mL of a 0.200 M acetic acid solution to make a buffer with pH = 5.00?
a. 20.22 mL
b. 7.17 mL
c. 19.02 mL
d. 3.94 mL
3) Calculate the pH of a 1.03 M potassium nitrite, KNO2, solution.
4) (Points: 1)
You may want to use the acid/base table provided to answer the question below
Which of the following acid-base pairs would work best for a laboratory experiment requiring a pH of 6.8? What molar ratios of the compounds would you use to prepare the solution?
a. 0.20 mol H2S / 0.13 mol HS-
b. 0.13 mol H2S / 0.20 mol HS-
c. 0.10 mol HCO3- / 0.26 mol CO32-
d. 0.26 mol HCO3- / 0.10 mol CO32-
Thanks so much!
Please help!
1) What mass of sodium nitrite must be added to 250 mL of a 0.200 M nitrous acid solution to make a buffer with pH = 3.00?
a. 30.90 g
b. 1.54 g
c. 3.44 g
d. 1.07 g
2) (Points: 1)
How many mL of 4.50 M sodium hydroxide must be added to 250 mL of a 0.200 M acetic acid solution to make a buffer with pH = 5.00?
a. 20.22 mL
b. 7.17 mL
c. 19.02 mL
d. 3.94 mL
3) Calculate the pH of a 1.03 M potassium nitrite, KNO2, solution.
4) (Points: 1)
You may want to use the acid/base table provided to answer the question below
Which of the following acid-base pairs would work best for a laboratory experiment requiring a pH of 6.8? What molar ratios of the compounds would you use to prepare the solution?
a. 0.20 mol H2S / 0.13 mol HS-
b. 0.13 mol H2S / 0.20 mol HS-
c. 0.10 mol HCO3- / 0.26 mol CO32-
d. 0.26 mol HCO3- / 0.10 mol CO32-
Thanks so much!