Transcript Naming Acids
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9.4 Naming and Writing Formulas for Acids and Bases >
Chapter 9 Chemical Names and Formulas 9.1 Naming Ions 9.2 Naming and Writing Formulas for Ionic Compounds 9.3 Naming and Writing Formulas for Molecular Compounds
9.4 Naming and Writing Formulas for Acids and Bases
9.5 The Laws Governing How Compounds Form Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
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9.4 Naming and Writing Formulas for Acids and Bases > CHEMISTRY & YOU What’s the name of the acid responsible for the crisp taste in this drink?
There’s a certain acid that gives many soft drinks their crisp, enjoyable taste.
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9.4 Naming and Writing Formulas for Acids and Bases >
Names and Formulas of Acids
Names and Formulas of Acids
How do you determine the name and formula of an acid?
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9.4 Naming and Writing Formulas for Acids and Bases >
Names and Formulas of Acids • Acids are a group of ionic compounds with unique properties.
• Acids can be defined in several ways.
• For now, it is enough to know that an
acid
is a compound that contains one or more hydrogen atoms and produces hydrogen ions when dissolved in water.
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9.4 Naming and Writing Formulas for Acids and Bases >
Names and Formulas of Acids • Acids have many uses.
• For example, sulfuric acid is often used to etch circuit boards like the one shown below.
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9.4 Naming and Writing Formulas for Acids and Bases >
Names and Formulas of Acids • Three rules can help you name an acid with the general formula H
n
X dissolved in water.
1. When the name of the anion ends in ide, the acid name begins with the prefix hydro-. The stem of the anion has the suffix -ic and is followed by the word acid.
• Therefore, HCl (X= chloride) is named
hydro
chloric
acid
.
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9.4 Naming and Writing Formulas for Acids and Bases >
Names and Formulas of Acids • Three rules can help you name an acid with the general formula H
n
X dissolved in water.
2. When the anion name ends in -ite, the acid name is the stem of the anion with the suffix -ous, followed by the word acid.
• Thus, H 2 SO 3 (X = sulfite) is named sulfur
ous acid
.
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9.4 Naming and Writing Formulas for Acids and Bases >
Names and Formulas of Acids • Three rules can help you name an acid with the general formula H
n
X dissolved in water.
3. When the anion name ends in -ate, the acid name is the stem of the anion with the suffix -ic, followed by the word acid.
• Thus, HNO 3 nitr
ic acid
.
(X = nitrate) is named Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
9.4 Naming and Writing Formulas for Acids and Bases >
Names and Formulas of Acids 9 These three rules for naming an acid with the general formula H
n
X dissolved in water are summarized in the table below.
Anion ending
-ide -ite -ate
Example Naming Common Acids Acid name
chlor
ide
, Cl – sulf
ite
, SO 3 – nitr
ate
, NO 3 –
hydro
-(stem) (stem) (stem)-
ic
acid
ous acid ic acid
Example
hydro
chlor
ic
acid sulfur
ous acid
nitr
ic acid
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9.4 Naming and Writing Formulas for Acids and Bases > CHEMISTRY & YOU An acid that provides the crisp taste in many soft drinks has the formula H 3 PO 4 . What’s the name of this acid?
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9.4 Naming and Writing Formulas for Acids and Bases > CHEMISTRY & YOU An acid that provides the crisp taste in many soft drinks has the formula H 3 PO 4 . What’s the name of this acid?
The name of this acid is phosphoric acid.
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9.4 Naming and Writing Formulas for Acids and Bases >
Names and Formulas of Acids
Writing Formulas of Acids To write the formula for an acid, use the rule for writing the name of the acid in reverse. Then, balance the ionic charges just as you would for any ionic compound.
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9.4 Naming and Writing Formulas for Acids and Bases >
Names and Formulas of Acids
Writing Formulas of Acids
• Many industrial processes, including steel and fertilizer manufacturing, use acids.
• You should become familiar with the names and formulas of common acids such as those listed in the table at right.
Common Acids Name Formula
Hydrochloric acid Sulfuric acid Nitric acid Ethanoic acid Phosphoric acid Carbonic acid HCl H 2 SO 4 HNO 3 HC 2 H 3 O 2 H 3 PO 4 H 2 CO 3 Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
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9.4 Naming and Writing Formulas for Acids and Bases > Sample
Problem 9.8
Naming Acids
Name the following compounds as acids.
a. HClO b. HCN Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
9.4 Naming and Writing Formulas for Acids and Bases > Sample
Problem 9.8
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1 Analyze Identify the relevant concepts.
The anion of the acid determines the acid name. (1) If the name of the anion ends in
-ide
, name the acid using the stem of the anion with the prefix
hydro
- and the suffix
-ic
, followed by the word
acid
. (2) If the anion name ends in
-ite
, name the acid using the stem of the anion with the suffix
-ous
, followed by the word
acid
. (3) If the anion name ends in
-ate
, name the acid using the stem of the anion with the suffix
-ic
, followed by the word
acid.
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9.4 Naming and Writing Formulas for Acids and Bases > Sample
Problem 9.8
2 Solve Apply concepts to this problem.
Identify the anion in the acid and the suffix of the anion name.
a. HClO: ClO – , (hypochlor ite ) 16 b. HCN: CN – , (cyan ide ) Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
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9.4 Naming and Writing Formulas for Acids and Bases > Sample
Problem 9.8
2 Solve Apply concepts to this problem.
Name the acid using the appropriate prefix (if any) and suffix. Finish with the word
acid
.
a. HClO: ClO – , (hypochlor ite ) hypochlorous acid (Rule 2) b. HCN: CN – , (cyan ide ) hydrocyanic acid (Rule 1) Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
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9.4 Naming and Writing Formulas for Acids and Bases > What is the name of the acid H 2 S?
(Hint: X = sulfide)
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9.4 Naming and Writing Formulas for Acids and Bases >
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What is the name of the acid H 2 S?
(Hint: X = sulfide)
H 2 S is named hydrosulfuric acid. Use Rule 1: When the name of the anion ends in
-ide
, the acid name begins with the prefix
hydro-
. The stem of the anion has the suffix
-ic
and is followed by the word
acid
.
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9.4 Naming and Writing Formulas for Acids and Bases >
Names and Formulas of Bases
Names and Formulas of Bases
How do you determine the name and formula of a base?
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9.4 Naming and Writing Formulas for Acids and Bases >
Names and Formulas of Bases • A
base
is generally an ionic compound that produces hydroxide ions when dissolved in water.
Bases are named in the same way as other ionic compounds —the name of the cation is followed by the name of the anion.
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9.4 Naming and Writing Formulas for Acids and Bases >
Names and Formulas of Bases 22 • The common base sodium hydroxide is used in making cleaners, soap, and paper, as shown in the figure at right.
• Sodium hydroxide (NaOH) is composed of sodium cations (Na + ) and hydroxide anions (OH – ).
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9.4 Naming and Writing Formulas for Acids and Bases >
Names and Formulas of Bases
To write the formula for a base, first write the symbol for the metal cation followed by the formula for the hydroxide ion. Then, balance the ionic charges just as you would for any ionic compound.
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9.4 Naming and Writing Formulas for Acids and Bases > Is the naming of a base more similar to the naming of an acid or to the naming of other ionic compounds?
Unlike acids, bases are named in the same way as other ionic compounds.
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9.4 Naming and Writing Formulas for Acids and Bases >
Glossary Terms •
acid
: a compound that produces hydrogen ions in solution; see also hydrogen-ion donor, Lewis acid •
base
: a compound that produces hydroxide ions in solution; see also hydrogen-ion acceptor, Lewis base Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
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9.4 Naming and Writing Formulas for Acids and Bases >
END OF 9.4
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