Question

1. What is the pH at the equivalence point in the titration of a 17.7 mL sample of a0.305 M aqueous nitrous acid solution with a 0.330 M aqueous sodium hydroxidesolution?

pH = ____

2. When a 18.1 mL sample of a 0.411 M aqueous nitrous acid solution is titrated with a 0.387 M aqueous potassium hydroxide solution, what is the pH at the midpoint in the titration?

pH = ____

3. A 27.4 mL sample of a 0.386 M aqueous hydrocyanic acid solution is titrated with a0.417 M aqueous sodium hydroxide solution. What is the pH at the start of the titration, before any sodium hydroxide has been added?

pH = _____