Concept explainers
Consider a buffered solution containing CH3NH3Cl and CH3NH2. Which of the following statements concerning this solution is(are) true? (Ka for CH3NH3+ = 2.3 × 10−11.)
a. A solution consisting of 0.10 M CH3NH3Cl and 0.10 M CH3NH2 would have a higher buffering capacity than one containing 1.0 M CH3NH3Cl and 1.0 M CH3NH2.
b. If [CH3NH2] > [CH3NH3+], then the pH is larger than the pKa value.
c. Adding more [CH3NH3Cl]to the initial buffer solution will decrease the pH.
d. If [CH3NH2] < [CH3NH3+],then pH < 3.36.
e. If [CH3NH2] = [CH3NH3+], then pH = 10.64.
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