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Aqueous Ionic Equilibrium

1- Consider the following titration curve of a weak acid titrated with strong base. At which point(s) on the graph is the solution a buffer? (see attachment for image)

2- Which of the following solutions has the highest buffer capacity? Choose from:
0.100 M NaCl / 0.100 M NaOH
pure H2O
0.050 M NaCN / 0.050 M HCN
0.100 M HCl / 0.100 M NaOH
0.025 M NaCN / 0.025 M HCN

3- A student adds solid silver chloride (AgCl) to each of two beakers: one containing 1.0 L of pure water, and one containing 1.0 L of 0.500 M NaCl. In which will AgCl be more soluble, and why? Choose from:
0.500 M NaCl: the sodium ions in the solution will complex with the chloride, allowing more AgCl to dissolve.
0.500 M NaCl: in the 0.500 M NaCl solution, the chloride ions that are already present will increase the amount of AgCl that dissolves by decreasing the value of
Neither: AgCl is completely insoluble, and will not dissolve in either.
Pure H2O: in the 0.500 M NaCl solution the chloride ions that are already present will inhibit the AgCl from dissolving by increasing the value of Q.
Both: AgCl is freely soluble in both.

4- Determine the pH of each solution.
0.16M KCHO 2
0.16M KCHO 2
0.25M KI

5- Ammonia, NH 3 , is a weak base with a K b value of 1.8×10 −5 .
What is the percent ionization of ammonia at this concentration?

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Chapter 16 (Aqueous Ionic Equilibrium) Questions Part II
1- Consider the following titration curve of a weak acid titrated with strong base. At which point(s) on the graph is the solution a buffer?

It is the half-equivalence point (point 2), at the mid of the buffered region where the pH barely changes for a lot of base added.
2- Which of the following solutions has the highest buffer capacity? Choose from:
A. 0.100 M NaCl / 0.100 M NaOH
B. pure H2O
C. 0.050 M NaCN / 0.050 M HCN
D. 0.100 M HCl / 0.100 M NaOH
E. 0.025 M NaCN / 0.025 M HCN

Eliminate anything that has a strong acid or base: In other words, eliminate A and D (NaOH is a strong base and HCl is a strong acid).

Eliminate B as it ...

Solution Summary

This solution provides logical answers and step-wise calculations pertained to buffers, solubility, pH and ionization.

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