In a hospital laboratory, a 10.0 mL sample of gastric juice, obtained several hours after a meal, was titrated with 0.1 M NaOH to neutrality; 7.2 mL of NaOH was required. The patient’s stomach contained no ingested food or drink; thus assume that no buffers were present. What was the pH of the gastric juice?

You add 7.00 mL of 0.100 M NaOH to 50.00 mL of pure water, and to this mixture you then add 12.00 mL of 0.800 M HCl. What will be the pH of the resulting solution?

A 37.0 mL sample of a 0.380 M aqueous hydrocyanic acid solution is titrated with a 0.464 M aqueous solution of barium hydroxide. How many milliliters of barium hydroxide must be added to reach a pH of 9.067?

A 39.0 mL sample of a 0.540 M aqueous hypochlorous acid solution is titrated with a 0.390 M aqueous solution of sodium hydroxide. How many milliliters of sodium hydroxide must be added to reach a pH of 7.176? mL

Explain the role of a buffer, such as an antacid table or sodium bicarbonate, on the pH of a solution ( like blood)

Consider the “window cleaner” problem, question 2 on page 12 of your lecture notes. Suppose that prior to the titration, the 10 mL sample of window cleaner was diluted by adding about 10 mL of DI water so that the solution could have better contact with the pH meter. What effect would this dilution have on the volume of titrant needed? (a) The amount of titrant would be the same because the moles of analyte was not changed.(b) The amount of titrant would be doubled because the analyte solution volume was doubled.(c) The amount of titrant would be halved because the was diluted by half.

Equal volumes of solutions of acids and their sodium salts are mixed to prepare a buffer. The solution with pH closest to 6.0 was prepared by mixing:

A patient is suspected of having low stomach acid, a condition known as hypochloridia. To determine whether the patient has this condition, her doctors take a 0.01534 L sample of her gastric juices and titrate the sample with 0.000185 M KOH. The gastric juice sample required 0.00645 L of the KOH titrant to neutralize it. Calculate the pH of the gastric juice sample. Assume the sample contained no ingested food or drink which might otherwise interfere with the titration.

A solution was prepared by mixing 50.0 mL of 0.10 M HCl and 25.0 mL of 0.25 M NaOH. What is the pH of the resulting solution?

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