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Problem 41d
Classify each acid as strong or weak. If the acid is weak, write an expression for the acid ionization constant (Ka). d. H2SO3
Problem 42a
Classify each acid as strong or weak. If the acid is weak, write an expression for the acid ionization constant (Ka). a. HF
Problem 42b
Classify each acid as strong or weak. If the acid is weak, write an expression for the acid ionization constant (Ka). b. HCHO2
Problem 42c
Classify each acid as strong or weak. If the acid is weak, write an expression for the acid ionization constant (Ka). c. H2SO4
Problem 42d
Classify each acid as strong or weak. If the acid is weak, write an expression for the acid ionization constant (Ka). d. H2CO3
- The three diagrams represent three different solutions of the binary acid HA. Water molecules have been omitted for clarity, and hydronium ions (H3O+) are represented by hydrogen ions (H+). Rank the acids in order of decreasing strength.
Problem 43
Problem 44
Rank the solutions in order of decreasing [H3O+]: 0.10 M HCl; 0.10 M HF; 0.10 M HClO; 0.10 M HC6H5O.
Problem 45c
Pick the stronger base from each pair. c. F– or ClO–
- Calculate the pH and pOH of each solution at 25 °C. a. [H3O+] = 1.7 × 10^-8 M b. [H3O+] = 1.0 × 10^-7 M c. [H3O+] = 2.2 × 10^-6 M
Problem 49
Problem 50a
Calculate [H3O+] and [OH–] for each solution at 25 °C. a. pH = 8.55
Problem 50b,c
Calculate [H3O+] and [OH–] for each solution at 25 °C. b. pH = 11.23 c. pH = 2.87
Problem 51
Complete the table. (All solutions are at 25 °C.)
Problem 52
Complete the table. (All solutions are at 25 °C.)
Problem 53
Like all equilibrium constants, the value of Kw depends on temperature. At body temperature (37 °C), Kw = 2.4×10–14. What are the [H3O+] and pH of pure water at body temperature?
Problem 54
The value of Kw increases with increasing temperature. Is the autoionization of water endothermic or exothermic?
Problem 54e
Determine whether or not the mixing of each pair of solutions results in a buffer. e. 105.0 mL of 0.15 M CH3NH2; 95.0 mL of 0.10 M HCl
Problem 55
Calculate the pH of each acid solution. Explain how the resulting pH values demonstrate that the pH of an acid solution should carry as many digits to the right of the decimal place as the number of significant figures in the concentration of the solution. [H3O+] = 0.044 M [H3O+] = 0.045 M [H3O+] = 0.046 M
Problem 56
Determine the concentration of H3O+ to the correct number of significant figures in a solution with each pH. Describe how these calculations show the relationship between the number of digits to the right of the decimal place in pH and the number of significant figures in concentration. pH = 2.50 pH = 2.51 pH = 2.52
Problem 57a
For each strong acid solution, determine [H3O+], [OH–], and pH. a. 0.25 M HCl
Problem 57b
For each strong acid solution, determine [H3O+], [OH–], and pH. b. 0.015 M HNO3
Problem 57c
For each strong acid solution, determine [H3O+], [OH–], and pH. c. a solution that is 0.052 M in HBr and 0.020 M in HNO3
Problem 57d
For each strong acid solution, determine [H3O+], [OH–], and pH. d. a solution that is 0.655% HNO3 by mass (assume a density of 1.01 g/mL for the solution)
Problem 59
What mass of HI must be present in 0.250 L of solution to obtain a solution with each pH value?
a. pH = 1.25 b. pH = 1.75 c. pH = 2.85
Problem 60
What mass of HClO4 must be present in 0.500 L of solution to obtain a solution with each pH value? a. pH = 2.50 b. pH = 1.50 c. pH = 0.50
Problem 61
What is the pH of a solution in which 224 mL of HCl(g), measured at 27.2 °C and 1.02 atm, is dissolved in 1.5 L of aqueous solution?
Problem 63
Determine the [H3O+] and pH of a 0.100 M solution of benzoic acid.
Problem 64
Determine the [H3O+] and pH of a 0.200 M solution of formic acid.
Problem 65
Determine the pH of an HNO2 solution of each concentration. In which cases can you not make the simplifying assumption that x is small? a. 0.500 M b. 0.100 M c. 0.0100 M
Problem 66
Determine the pH of an HF solution of each concentration. In which cases can you not make the simplifying assumption that x is small? (Ka for HF is 6.8×10–4.) a. 0.250 M b. 0.0500 M c. 0.0250 M
Problem 69
A 0.185 M solution of a weak acid (HA) has a pH of 2.95. Calculate the acid ionization constant (Ka) for the acid.