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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
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Acid-Base Theories >
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Acid-Base Theories >Acid-Base Theories > Properties of Acids and Bases
Properties of Acids and Bases
What are the properties of acids and bases?
19.1
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Acid-Base Theories >Acid-Base Theories >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.
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Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories > Properties of Acids and Bases
Citrus fruits contain citric acid. Tea contains tannic acid.
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Acid-Base Theories >Acid-Base Theories >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
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Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >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.
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Acid-Base Theories >Acid-Base Theories >Acid-Base Theories > Arrhenius Acids and Bases
Arrhenius Acids and Bases
How did Arrhenius define an acid and a base?
19.1
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Acid-Base Theories >Acid-Base Theories >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.
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Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >19.1 Arrhenius Acids and Bases
Hydrochloric Acid
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Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories > Arrhenius Acids and Bases19.1
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Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >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.
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Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories > Arrhenius Acids and Bases19.1
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Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories > Arrhenius Acids and Bases
Milk of magnesia is a base used as an antacid.
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Acid-Base Theories >
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Acid-Base Theories >Acid-Base Theories > Brønsted-Lowry Acids and Bases
Brønsted-Lowry Acids and Bases
What distinguishes an acid from a base in the Brønsted-Lowry theory?
19.1
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Acid-Base Theories >Acid-Base Theories >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.
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Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories > Brønsted-Lowry Acids and Bases19.1
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Acid-Base Theories >
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Acid-Base Theories >Acid-Base Theories > Lewis Acids and Bases
Lewis Acids and Bases
How did Lewis define an acid and a base?
19.1
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Acid-Base Theories >Acid-Base Theories >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.
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Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >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.
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Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories >Acid-Base Theories > Lewis Acids and Bases19.1
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Practice Problems for Conceptual Problem 19.1
Problem Solving 19.1
Solve Problem 1 with the help of an interactive guided tutorial.
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Section Quiz
-or-Continue to: Launch:
Assess students’ understanding of the concepts in Section
19.1 Section Quiz.
19.1.
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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.
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2. Which compound is most likely to act as an Arrhenius acid?
a. H2O
b. NH3.
c. NaOH.
d. H2SO4.
19.1 Section Quiz.
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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.