Problema 53e
Determine whether or not the mixing of each pair of solutions results in a buffer. e. 125.0 mL of 0.15 M NH3; 150.0 mL of 0.20 M NaOH
Problema 54b
Determine whether or not the mixing of each pair of solutions results in a buffer. a. 75.0 mL of 0.10 M HF; 55.0 mL of 0.15 M NaF b. 150.0 mL of 0.10 M HF; 135.0 mL of 0.175 M HCl d. 125.0 mL of 0.15 M CH3NH2; 120.0 mL of 0.25 M CH3NH3Cl
Problema 54c
Determine whether or not the mixing of each pair of solutions results in a buffer. c. 165.0 mL of 0.10 M HF; 135.0 mL of 0.050 M KOH
Problema 55a
Blood is buffered by carbonic acid and the bicarbonate ion. Normal blood plasma is 0.024 M in HCO3- and 0.0012 M H2CO3 (pKa1 for H2CO3 at body temperature is 6.1).
a. What is the pH of blood plasma?
Problema 55c
Blood is buffered by carbonic acid and the bicarbonate ion. Normal blood plasma is 0.024 M in HCO3- and 0.0012 M H2CO3 (pKa1 for H2CO3 at body temperature is 6.1).
c. Given the volume from part (b), what mass of NaOH can be neutralized before the pH rises above 7.8?
Problema 56
The fluids within cells are buffered by H2PO4- and HPO42- . b. Could a buffer system employing H3PO4 as the weak acid and H2PO4- as the weak base be used as a buffer system within cells? Explain.
- Which buffer system is the best choice to create a buffer with pH = 7.20? For the best system, calculate the ratio of the masses of the buffer components required to make the buffer: HC2H3O2/KC2H3O2, HClO2/KClO2, NH3/NH4Cl, or HClO/KClO.
Problema 57
Problema 58
Which buffer system is the best choice to create a buffer with pH = 9.00? For the best system, calculate the ratio of the masses of the buffer components required to make the buffer. HF/KF HNO2/KNO2 NH3/NH4Cl HClO/KClO
Problema 59a
A 500.0-mL buffer solution is 0.100 M in HNO2 and 0.150 M in KNO2. Determine if each addition would exceed the capacity of the buffer to neutralize it. a. 250 mg NaOH
Problema 59b
A 500.0-mL buffer solution is 0.100 M in HNO2 and 0.150 M in KNO2. Determine if each addition would exceed the capacity of the buffer to neutralize it. b. 350 mg KOH
Problema 59c
A 500.0-mL buffer solution is 0.100 M in HNO2 and 0.150 M in KNO2. Determine if each addition would exceed the capacity of the buffer to neutralize it. c. 1.25 g HBr
Problema 59d
A 500.0-mL buffer solution is 0.100 M in HNO2 and 0.150 M in KNO2. Determine if each addition would exceed the capacity of the buffer to neutralize it. d. 1.35 g HI
Problema 60
A 1.0-L buffer solution is 0.125 M in HNO2 and 0.145 M in NaNO2. Determine the concentrations of HNO2 and NaNO2 after the addition of each substance: a. 1.5 g HCl b. 1.5 g NaOH c. 1.5 g HI
Problema 61a
The graphs labeled (a) and (b) show the titration curves for two equal-volume samples of monoprotic acids, one weak and one strong. Both titrations were carried out with the same concentration of strong base.
(i) What is the approximate pH at the equivalence point of each curve?
Problema 61b
The graphs labeled (a) and (b) show the titration curves for two equal-volume samples of monoprotic acids, one weak and one strong. Both titrations were carried out with the same concentration of strong base.
(ii) Which graph corresponds to the titration of the strong acid and which one to the titration of the weak acid?
- Two 25.0-mL samples, one 0.100 M HCl and the other 0.100 M HF, are titrated with 0.200 M KOH. a. What is the volume of added base at the equivalence point for each titration?
Problema 62
Problema 62b
Two 25.0-mL samples, one 0.100 M HCl and the other 0.100 M HF, are titrated with 0.200 M KOH. b. Is the pH at the equivalence point for each titration acidic, basic, or neutral?
Problema 62c
Two 25.0-mL samples, one 0.100 M HCl and the other 0.100 M HF, are titrated with 0.200 M KOH. c. Which titration curve has the lower initial pH?
Problema 62d
Two 25.0-mL samples, one 0.100 M HCl and the other 0.100 M HF, are titrated with 0.200 M KOH.
d. Sketch each titration curve.
Problema 63a
Two 20.0-mL samples, one 0.200 M KOH and the other 0.200 M CH3NH2, are titrated with 0.100 M HI. a. What is the volume of added acid at the equivalence point for each titration?
Problema 63b
Two 20.0-mL samples, one 0.200 M KOH and the other 0.200 M CH3NH2, are titrated with 0.100 M HI. b. Is the pH at the equivalence point for each titration acidic, basic, or neutral?
Problema 63c
Two 20.0-mL samples, one 0.200 M KOH and the other 0.200 M CH3NH2, are titrated with 0.100 M HI. c. Which titration curve has the lower initial pH?
Problema 63d
Two 20.0-mL samples, one 0.200 M KOH and the other 0.200 M CH3NH2, are titrated with 0.100 M HI. d. Sketch each titration curve.
Problema 64b
The graphs labeled (a) and (b) show the titration curves for two equal-volume samples of bases, one weak and one strong. Both titrations were carried out with the same concentration of strong acid.
(ii) Which graph corresponds to the titration of the strong base and which one to the weak base?
Problema 65c
Consider the curve shown here for the titration of a weak monoprotic acid with a strong base and answer each question.
c. At what volume of added base does pH = pKa?
Problema 65d
Consider the curve shown here for the titration of a weak monoprotic acid with a strong base and answer each question.
d. At what volume of added base is the pH calculated by working an equilibrium problem based on the concentration and Kb of the conjugate base?
Problema 66a
Consider the curve shown here for the titration of a weak base with a strong acid and answer each question.
a. What is the pH and what is the volume of added acid at the equivalence point?
Problema 66c
Consider the curve shown here for the titration of a weak base with a strong acid and answer each question.
c. At what volume of added acid does pH = 14 - pKb?
Problema 66d
Consider the curve shown here for the titration of a weak base with a strong acid and answer each question.
d. At what volume of added acid is the pH calculated by working an equilibrium problem based on the concentration and Ka of the conjugate acid?
Problema 67a
Consider the titration of a 35.0-mL sample of 0.175 M HBr with 0.200 M KOH. Determine each quantity. a. the initial pH
Ch.18 - Aqueous Ionic Equilibrium
