Indietro
- Predict whether a precipitate will form if you mix 175.0 mL of a 0.0055 M KCl solution with 145.0 mL of a 0.0015 M AgNO3 solution, and identify the precipitate, if any.
Problema 11
- Calculate the pH of a solution made by combining 10.0 mL of 17.5 M acetic acid with 5.54 g of sodium acetate and diluting to a total volume of 1.50 L.
Problema 12
- What is the mass of sodium formate required to be dissolved in 250.0 cm³ of a 1.4 M formic acid solution to prepare a buffer solution with a pH of 3.36?
Problema 14
Problema 27
In which of these solutions will HNO2 ionize less than it does in pure water? a. 0.10 M NaCl b. 0.10 M KNO3 c. 0.10 M NaOH d. 0.10 M NaNO2
Problema 28
A formic acid solution has a pH of 3.25. Which of these substances will raise the pH of the solution upon addition? Explain your answer. a. HCl b. NaBr c. NaCHO2 d. KCl
Problema 29a
Solve an equilibrium problem (using an ICE table) to calculate the pH of each solution. a. a solution that is 0.25 M in NH3 and 0.18 M in NH4Cl
Problema 29b
Solve an equilibrium problem (using an ICE table) to calculate the pH of each solution. b solution that is 0.15 M in HCHO2 and 0.25 M in NaCHO2
Problema 31
Calculate the percent ionization of a 0.20 M benzoic acid solution in pure water and in a solution containing 0.25 M sodium benzoate. Why does the percent ionization differ significantly in the two solutions?
Problema 33a
Solve an equilibrium problem (using an ICE table) to calculate the pH of each solution. a. 0.15 M HF
Problema 33b
Solve an equilibrium problem (using an ICE table) to calculate the pH of each solution. b. 0.15 M NaF
Problema 33c
Solve an equilibrium problem (using an ICE table) to calculate the pH of each solution. c. a mixture that is 0.15 M in HF and 0.15 M in NaF
Problema 35
A buffer contains significant amounts of acetic acid and sodium acetate. Write equations showing how this buffer neutralizes added acid and added base.
Problema 36
A buffer contains significant amounts of ammonia and ammonium chloride. Write equations showing how this buffer neutralizes added acid and added base.
Problema 37
Use the Henderson–Hasselbalch equation to calculate the pH of each solution in Problem 29.
Problema 39c
Use the Henderson–Hasselbalch equation to calculate the pH of each solution. c. a solution that contains 10.0 g of HC2H3O2 and 10.0 g of NaC2H3O2 in 150.0 mL of solution
Problema 41a
Calculate the pH of the solution that results from each mixture. a. 50.0 mL of 0.15 M HCHO2 with 75.0 mL of 0.13 M NaCHO2
Problema 41b
Calculate the pH of the solution that results from each mixture. b. 125.0 mL of 0.10 M NH3 with 250.0 mL of 0.10 M NH4Cl
Problema 43
Calculate the ratio of NaF to HF required to create a buffer with pH = 3.90.
Problema 44
Calculate the ratio of CH3NH2 to CH3NH3Cl concentration required to create a buffer with pH=10.34.
Problema 45
What mass of sodium benzoate should you add to 150.0 mL of a 0.15 M benzoic acid solution to obtain a buffer with a pH of 4.25? (Assume no volume change.)
Problema 46
Pick the stronger base from each pair. a. ClO4– or ClO2– b. Cl– or H2O c. CN– or ClO–
- A 250.0-mL buffer solution is 0.250 M in acetic acid and 0.250 M in sodium acetate. a. What is the initial pH of this solution? b. What is the pH after the addition of 0.0050 mol of HCl? c. What is the pH after the addition of 0.0050 mol of NaOH?
Problema 47
Problema 48a
A 100.0-mL buffer solution is 0.175 M in HClO and 0.150 M in NaClO. a. What is the initial pH of this solution?
Problema 48b
A 100.0-mL buffer solution is 0.175 M in HClO and 0.150 M in NaClO. b. What is the pH after addition of 150.0 mg of HBr?
Problema 48c
A 100.0-mL buffer solution is 0.175 M in HClO and 0.150 M in NaClO. c. What is the pH after addition of 85.0 mg of NaOH?
- For each solution, calculate the initial and final pH after adding 0.010 mol of HCl: a. 500.0 mL of pure water b. 500.0 mL of a buffer solution that is 0.125 M in HC2H3O2 and 0.115 M in NaC2H3O2 c. 500.0 mL of a buffer solution that is 0.155 M in C2H5NH2 and 0.145 M in C2H5NH3Cl.
Problema 51
Problema 52
For each solution, calculate the initial and final pH after adding 0.010 mol of NaOH. a. 250.0 mL of pure water b. 250.0 mL of a buffer solution that is 0.195 M in HCHO2 and 0.275 M in KCHO2 c. 250.0 mL of a buffer solution that is 0.255 M in CH3CH2NH2 and 0.235 M in CH3CH2NH3Cl
- A 350.0-mL buffer solution is 0.150 M in HF and 0.150 M in NaF. What mass of NaOH can this buffer neutralize before the pH rises above 4.00? If the same volume of the buffer were 0.350 M in HF and 0.350 M in NaF, what mass of NaOH could be handled before the pH rises above 4.00?
Problema 53
Problema 54
A 100.0-mL buffer solution is 0.100 M in NH3 and 0.125 M in NH4Br. What mass of HCl can this buffer neutralize before the pH falls below 9.00?
Problema 54d
Determine whether or not the mixing of each pair of solutions results in a buffer. d. 105.0 mL of 0.12 M CH3NH2 ; 110.0 mL of 0.15 M CH3NH3Cl