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Acid-Base Theories. 19.1. 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.
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Acid-Base Theories 19.1 • 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 Properties of Acids and Bases • Properties of Acids and Bases • What are the properties of acids and bases?
19.1 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 Properties of Acids and Bases • Citrus fruits contain citric acid. Tea contains tannic acid.
19.1 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 Properties of Acids and Bases • Antacids use bases to neutralize excess stomach acid. The base calcium hydroxide is a component of mortar.
19.1 Arrhenius Acids and Bases • Arrhenius Acids and Bases • How did Arrhenius define an acid and a base?
19.1 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 Arrhenius Acids and Bases • Hydrochloric Acid
19.1 Arrhenius Acids and Bases
19.1 Arrhenius Acids and Bases • Arrhenius Bases • Hydroxide ions are one of the products of the dissolution of an alkali metal in water.
19.1 Arrhenius Acids and Bases
19.1 Arrhenius Acids and Bases • Milk of magnesia is a base used as an antacid.
19.1 Brønsted-Lowry Acids and Bases • Brønsted-Lowry Acids and Bases • What distinguishes an acid from a base in the Brønsted-Lowry theory?
19.1 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 Brønsted-Lowry Acids and Bases
19.1 Lewis Acids and Bases • Lewis Acids and Bases • How did Lewis define an acid and a base?
19.1 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 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 Lewis Acids and Bases
for Conceptual Problem 19.1 • Problem Solving 19.1 • Solve Problem 1 with the help of an interactive guided tutorial.
19.1 Section Quiz. • 19.1.
19.1 Section Quiz. • 1. Which of the following is NOT a characteristic of acids? • taste sour • are electrolytes • feel slippery • affect the color of indicators
19.1 Section Quiz. • 2. Which compound is most likely to act as an Arrhenius acid? • H2O • NH3. • NaOH. • H2SO4.
19.1 Section Quiz. • 3. A Lewis acid is any substance that can accept • a hydronium ion. • a proton. • hydrogen. • a pair of electrons.