Chapter 15, Problem 15.19QP

Acids

You make a solution by dissolving 0.0010 mol of HCl in enough water to make 1.0 L of solution.

1. a Write the chemical equation for the reaction of HCl(aq) and water.
2. b Without performing calculations, give a rough estimate of the pH of the HCl solution. Justify your answer.
3. c Calculate the H₃O⁺ concentration and the pH of the solution.
4. d Is there any concentration of the base OH⁻ present in this solution of HCl(aq)? If so, where did it come from?
5. e If you increase the OH⁻ concentration of the solution by adding NaOH, does the H₃O⁺ concentration change? If you think it does, explain why this change occurs and whether the H₃O⁺ concentration increases or decreases.
6. f If you were to measure the pH of 10 drops of the original HCl solution, would you expect it to be different from the pH of the entire sample? Explain.
7. g Explain how two different volumes of your original HCl solution can have the same pH yet contain different moles of H₃O⁺.
8. h If 1.0 L of pure water were added to the HCl solution, would this have any impact on the pH? Explain.