Problem 103
How is a buffered solution different from a weak acid or a weak base dissolved in water?
Problem 104
What types of substances make good buffers?
Problem 105
What is the role of a buffer system in human blood?
Problem 106
How does the \(\mathrm{pH}\) change when an acid or base is added to a buffered solution?
Problem 109
A buffer system used to maintain solution pH values around 12 to 13 is prepared by adding similar concentrations of \(\mathrm{Na}_{2} \mathrm{HPO}_{4}\) and \(\mathrm{Na}_{3} \mathrm{PO}_{4}\) to water. (a) Write a balanced equation showing the acid and conjugate base in equilibrium. Omit spectator ions. (b) Describe how this buffer system prevents large \(\mathrm{pH}\) changes when an acid is added.
Problem 110
A buffer system used to maintain solution pH values around 5 is prepared by adding similar concentrations of \(\mathrm{CH}_{3} \mathrm{CO}_{2} \mathrm{H}\) and \(\mathrm{NaCH}_{3} \mathrm{CO}_{2}\) to water. (a) Write a balanced equation showing the acid and conjugate base in equilibrium. Omit spectator ions. (b) Describe how this buffer system prevents large \(\mathrm{pH}\) changes when a base is added.
Problem 111
Which of the following, when added to water, form a buffered solution? (a) \(\mathrm{HOCl}\) and \(\mathrm{NaCl}\) (b) \(\mathrm{HNO}_{2}\) and \(\mathrm{KNO}_{2}\) (c) \(\mathrm{CH}_{3} \mathrm{NH}_{2}\) and \(\mathrm{CH}_{3} \mathrm{NH}_{3} \mathrm{Cl}\)
Problem 112
Which of the following, when added to water, form a buffered solution? (a) \(\mathrm{HF}\) and \(\mathrm{NaF}\) (b) \(\mathrm{HI}\) and \(\mathrm{KI}\) (c) \(\mathrm{HOCl}\) and \(\mathrm{NaOCl}\)
Problem 113
The bicarbonate buffer system operates in the body's extracellular fluid by the following process: $$ \begin{array}{r} \mathrm{CO}_{2}(g)+\mathrm{H}_{2} \mathrm{O}(l) \Longrightarrow \mathrm{H}_{2} \mathrm{CO}_{3}(a q) \Longrightarrow \\ \mathrm{HCO}_{3}^{-}(a q)+\mathrm{H}^{+}(a q) \end{array} $$ What is expected to happen to the blood pH if the lungs are unable to expel \(\mathrm{CO}_{2}\) at the same rate as the body produces it? Describe what happens in terms of Le Chatelier's principle.
Problem 115
Why is \(\mathrm{NH}_{3}\) a base but \(\mathrm{CH}_{4}\) is not? Is it possible for \(\mathrm{CH}_{4}\) to act as a Bronsted-Lowry base?
