Chemistry 19.4

Neutralization Reactions 19.4 Excess hydrochloric acid in the stomach can cause heartburn and a feeling of nausea. Antacids neutralize the stomach acid and relieve the pain of acid indigestion. You will learn what a neutralization reaction is.

19.4 Acid-Base Reactions Acid-Base Reactions What are the products of the reaction of an acid with a base?

19.4 Acid-Base Reactions In general, the reaction of an acid with a base produces water and one of a class of compounds called salts.

19.4 Acid-Base Reactions Reactions in which an acid and a base react in an aqueous solution to produce a salt and water are generally called neutralization reactions.

19.4 Acid-Base Reactions

19.4 Titration Titration What is the endpoint of a titration?

The point of neutralization is the end point of the titration. 19.4 Titration The process of adding a known amount of solution of known concentration to determine the concentration of another solution is called titration. The point of neutralization is the end point of the titration.

19.4 Titration When an acid and base are mixed, the equivalence point is when the number of moles of hydrogen ions equals the number of moles of hydroxide ions.

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Solve Problem 30 with the help of an interactive guided tutorial. for Sample Problem 19.6 Sample Problem 19.6 Problem Solving 19.30 Solve Problem 30 with the help of an interactive guided tutorial.

The solution of known concentration is called the standard solution. 19.4 Titration The solution of known concentration is called the standard solution. Indicators are often used to determine when enough of the standard solution has been added to neutralize the acid or base. The point at which the indicator changes color is the end point of the titration.

Added base is measured with a buret. 19.4 Titration The titration of an acid with a base is shown here. a) A known volume of an acid (plus a few drops of phenolphthalein indicator) in a flask is placed beneath a buret filled with a base of known concentration. b) Base is slowly added from the buret to the acid while the flask is gently swirled. c) A change in the color of the indicator signals that neutralization has occurred. Added base is measured with a buret. Color change shows neutralization. Acid solution with indicator

Titration Simulation 26 Simulate the titration of several acids and bases and observe patterns in the pH at equivalence.

19.4 Titration In this titration of a strong acid with a strong base, 0.10M NaOH is slowly added from a buret to 50.0 mL of 0.10M HCl in the beaker. The equivalence point, the midpoint on the vertical portion of the pH titration curve, occurs at 50.0 mL of NaOH added. Interpreting Diagrams What is true concerning [H+] and [OH-] at the equivalence point?

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Solve Problem 33 with the help of an interactive guided tutorial. for Sample Problem 19.7 Problem Solving 19.33 Solve Problem 33 with the help of an interactive guided tutorial. Sample problem 19.7

19.4 Section Quiz. 19.4.

19.4 Section Quiz 1. When a neutralization takes place, one of the products is always carbon dioxide. a salt. sodium chloride. a precipitate.

19.4 Section Quiz 2. In a titration, 45.0 mL of KOH is neutralized by 75.0 mL of 0.30M HBr. What is the concentration of the KOH solution? 0.18M 0.60M 0.25M 0.50M

19.4 Section Quiz 3. How many moles of HCl are required to neutralize an aqueous solution of 2.0 mol Ca(OH)2? 0.5 mol 1.0 mol 2.0 mol 4.0 mol

19.4 Section Quiz 4. In which of the following neutralization titrations of 1-molar solutions of H2SO4 and NaOH will the equivalence point be reached at the very end of the additions? H2SO4(aq) + 2NaOH(aq)  Na2SO4(aq) + 2H2O(aq) 200 mL of H2SO4 is slowly added to 100 mL of NaOH 200 mL of H2SO4 is slowly added to 200 mL of NaOH 100 mL of H2SO4 is slowly added to 200 mL of NaOH 100 mL of H2SO4 is slowly added to 100 mL of NaOH

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