1. © Copyright Pearson Prentice Hall Slide 1 of 35 Acid-Base Theories Bracken Cave, near San Antonio, Texas, is home to twenty to forty million bats. Visitors to the cave must protect themselves from the dangerous levels of ammonia in the cave. Ammonia is a byproduct of the bats’ urine. You will learn why ammonia is considered a base. 19.1

2. © Copyright Pearson Prentice Hall Acid-Base Theories > Slide 2 of 35 Acid-Base Theories > > Properties of Acids and Bases What are the properties of acids and bases? 19.1

3. Slide 3 of 35 © Copyright Pearson Prentice Hall Acid-Base Theories > > > Properties of Acids and Bases Acids Acids taste sour, will change the color of an acid-base indicator, and can be strong or weak electrolytes in aqueous solution. 19.1

4. Slide 4 of 35 © Copyright Pearson Prentice Hall Acid-Base Theories > > > > > > Properties of Acids and Bases Citrus fruits contain citric acid. Tea contains tannic acid. 19.1

5. Slide 5 of 35 © Copyright Pearson Prentice Hall Acid-Base Theories > > > Properties of Acids and Bases Bases Bases taste bitter, feel slippery, will change the color of an acid-base indicator, and can be strong or weak electrolytes in aqueous solution. 19.1

6. Slide 6 of 35 © Copyright Pearson Prentice Hall Acid-Base Theories > > > > > > Properties of Acids and Bases Antacids use bases to neutralize excess stomach acid. The base calcium hydroxide is a component of mortar. 19.1

7. Slide 7 of 35 © Copyright Pearson Prentice Hall Acid-Base Theories > > > Arrhenius Acids and Bases How did Arrhenius define an acid and a base? 19.1

8. © Copyright Pearson Prentice Hall Slide 8 of 35 Acid-Base Theories > > > Arrhenius Acids and Bases Arrhenius said that acids are hydrogen- containing compounds that ionize to yield hydrogen ions (H + ) in aqueous solution. He also said that bases are compounds that ionize to yield hydroxide ions (OH – ) in aqueous solution. 19.1

9. Slide 9 of 35 © Copyright Pearson Prentice Hall Acid-Base Theories > > > > > > 19.1 Arrhenius Acids and Bases Hydrochloric Acid

10. Slide 10 of 35 © Copyright Pearson Prentice Hall Acid-Base Theories > > > > > > Arrhenius Acids and Bases 19.1

11. Slide 11 of 35 © Copyright Pearson Prentice Hall Acid-Base Theories > > > > > > Arrhenius Acids and Bases Arrhenius Bases Hydroxide ions are one of the products of the dissolution of an alkali metal in water. 19.1

12. Slide 12 of 35 © Copyright Pearson Prentice Hall Acid-Base Theories > > > > > > Arrhenius Acids and Bases 19.1

13. Slide 13 of 35 © Copyright Pearson Prentice Hall Acid-Base Theories > > > > > > Arrhenius Acids and Bases Milk of magnesia is a base used as an antacid. 19.1

14. © Copyright Pearson Prentice Hall Acid-Base Theories > Slide 14 of 35 Acid-Base Theories > > Brønsted-Lowry Acids and Bases What distinguishes an acid from a base in the Brønsted-Lowry theory? 19.1

15. © Copyright Pearson Prentice Hall Slide 15 of 35 Acid-Base Theories > > > Brønsted-Lowry Acids and Bases The Brønsted-Lowry theory defines an acid as a hydrogen-ion donor, and a base as a hydrogen-ion acceptor. 19.1

16. Slide 16 of 35 © Copyright Pearson Prentice Hall Acid-Base Theories > > > > > > Brønsted-Lowry Acids and Bases 19.1

17. © Copyright Pearson Prentice Hall Acid-Base Theories > Slide 17 of 35 Acid-Base Theories > > Lewis Acids and Bases How did Lewis define an acid and a base? 19.1

18. © Copyright Pearson Prentice Hall Slide 18 of 35 Acid-Base Theories > > > Lewis Acids and Bases Lewis proposed that an acid accepts a pair of electrons during a reaction, while a base donates a pair of electrons. 19.1

19. Slide 19 of 35 © Copyright Pearson Prentice Hall Acid-Base Theories > > > > > > Lewis Acids and Bases A Lewis acid is a substance that can accept a pair of electrons to form a covalent bond. A Lewis base is a substance that can donate a pair of electrons to form a covalent bond. 19.1

20. Slide 20 of 35 © Copyright Pearson Prentice Hall Acid-Base Theories > > > > > > Lewis Acids and Bases 19.1

21. © Copyright Pearson Prentice Hall Slide 21 of 35 Acid-Base Theories >

22. © Copyright Pearson Prentice Hall Slide 22 of 35 Acid-Base Theories >

23. © Copyright Pearson Prentice Hall Slide 23 of 35 Acid-Base Theories >

24. © Copyright Pearson Prentice Hall Slide 24 of 35 Practice Problems for Conceptual Problem 19.1 Problem Solving 19.1 Solve Problem 1 with the help of an interactive guided tutorial.

25. © Copyright Pearson Prentice Hall Slide 25 of 35 Section Quiz -or- Continue to: Launch: Assess students’ understanding of the concepts in Section 19.1 Section Quiz. 19.1.

26. © Copyright Pearson Prentice Hall Slide 26 of 35 1. Which of the following is NOT a characteristic of acids? a.taste sour b.are electrolytes c.feel slippery d.affect the color of indicators 19.1 Section Quiz.

27. © Copyright Pearson Prentice Hall Slide 27 of 35 2. Which compound is most likely to act as an Arrhenius acid? a.H 2 O b.NH 3. c.NaOH. d.H 2 SO 4. 19.1 Section Quiz.

28. © Copyright Pearson Prentice Hall Slide 28 of 35 19.1 Section Quiz. 3. A Lewis acid is any substance that can accept a.a hydronium ion. b.a proton. c.hydrogen. d.a pair of electrons.

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