Chapter 14
202-NYB-05
14.1 How an Acid and Base is
Defined
• Arrhenius Model:
• Acids produce H+ ions in solution
• bases produce OH– ions.
• Brønsted–Lowry Model:
• Acids are proton (H+) donors
• bases are proton acceptors.doesn'thave basecouldbe anynegativeion
tohaveon anything canbeabase
HCl + H2O → Cl– + H3O+
acid base
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, 14.1
A conjugate Acid-Base
Pair ofthe result
nation
HA(aq) + H2O(l) H3O+(aq) + A–(aq)
o O 0
acid base conjugate conjugate
acid base
always1gpt
• Conjugate base is everything that remains of the acid molecule
after a proton is lost.
• Conjugate acid is formed when the proton is transferred to the
base.
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14.1
Brønsted
Brønsted
Acid Conjugate Acid Conjugate
Base
base
• Water acts as a base accepting a proton from the acid.
• Forms hydronium ion (H3O+).
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reserved
, 14.1
Acids and Bases
Unlike the Arrhenius definition of acids & bases, the
Brønsted-Lowry model is not limited to aqueous
solutions. ionic cpd
a
NH3(g) + HCl(g) NH4Cl(s)
Acid
Conjugate
Bas Conjugate base
e 5
acid
Ionic compound : Electrostatic charge attraction between two oppositely charged ions
14.1
Try one
Which of the following represent conjugate acid–base pairs?
a) HCl, HNO3
b) H3O+, OH–
c) H2SO4, SO42–
d) HCN, CN– move Ht
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reserved
, 14.1
Exercise
Aniline, C6H5NH2, was isolated in the 1800s and began
immediate use in the dye industry. What is the formula of
the conjugate acid of this base?
1. C6H5NH2+
2. C6H5NH3+ gainof Ht
3. C6H5NH–
4. C6H5NH+
7
14.2
Acids and Bases
Relative Acid Strength
inverse
always Weak
Strong Conjugate
Acid base
HA(aq) + H2O(l) H3O+(aq) + A-(aq)
For a strong acid,
this equilibrium lies
to the right.
8
202-NYB-05
14.1 How an Acid and Base is
Defined
• Arrhenius Model:
• Acids produce H+ ions in solution
• bases produce OH– ions.
• Brønsted–Lowry Model:
• Acids are proton (H+) donors
• bases are proton acceptors.doesn'thave basecouldbe anynegativeion
tohaveon anything canbeabase
HCl + H2O → Cl– + H3O+
acid base
Copyright © Cengage Learning. All rights
2
reserved
, 14.1
A conjugate Acid-Base
Pair ofthe result
nation
HA(aq) + H2O(l) H3O+(aq) + A–(aq)
o O 0
acid base conjugate conjugate
acid base
always1gpt
• Conjugate base is everything that remains of the acid molecule
after a proton is lost.
• Conjugate acid is formed when the proton is transferred to the
base.
Copyright © Cengage Learning. All rights
3
reserved
14.1
Brønsted
Brønsted
Acid Conjugate Acid Conjugate
Base
base
• Water acts as a base accepting a proton from the acid.
• Forms hydronium ion (H3O+).
Copyright © Cengage Learning. All rights
4
reserved
, 14.1
Acids and Bases
Unlike the Arrhenius definition of acids & bases, the
Brønsted-Lowry model is not limited to aqueous
solutions. ionic cpd
a
NH3(g) + HCl(g) NH4Cl(s)
Acid
Conjugate
Bas Conjugate base
e 5
acid
Ionic compound : Electrostatic charge attraction between two oppositely charged ions
14.1
Try one
Which of the following represent conjugate acid–base pairs?
a) HCl, HNO3
b) H3O+, OH–
c) H2SO4, SO42–
d) HCN, CN– move Ht
Copyright © Cengage Learning. All rights
6
reserved
, 14.1
Exercise
Aniline, C6H5NH2, was isolated in the 1800s and began
immediate use in the dye industry. What is the formula of
the conjugate acid of this base?
1. C6H5NH2+
2. C6H5NH3+ gainof Ht
3. C6H5NH–
4. C6H5NH+
7
14.2
Acids and Bases
Relative Acid Strength
inverse
always Weak
Strong Conjugate
Acid base
HA(aq) + H2O(l) H3O+(aq) + A-(aq)
For a strong acid,
this equilibrium lies
to the right.
8