Acids and Bases

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Acids and Bases
http//www.unit5.org/chemistry/AcidBase.html
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Acid Base ? Salt Water

• Orange juice milk ? bad taste
• Evergreen shrub concrete ? dead bush
• Under a pine tree fertilizer ? white powder
• HCl NaOH ? NaCl HOH

salt water
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Acid-Base Neutralization


Dorin, Demmin, Gabel, Chemistry The Study of
Matter 3rd Edition, page 584
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Acid-Base Neutralization
1-
1


OH-
H2O
H3O
H2O
Hydroxide ion
Water
Hydronium ion
Water
Dorin, Demmin, Gabel, Chemistry The Study of
Matter 3rd Edition, page 584
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Neutralization
Neutralization is a chemical reaction between an
acid and a base to produce a salt (an
ionic compound) and water.
base
acid
salt
water
Some neutralization reactions
Na2SO4
HOH
2
H2SO4(aq) NaOH(aq)
2
sulfuric acid
sodium hydroxide
sodium sulfate
water
Ca(C2H3O2)2
HOH
2
HC2H3O2(aq) Ca(OH)2(aq)
2
acetic acid
calcium hydroxide
calcium acetate
water
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Neutralization

• ACID BASE ? SALT WATER

HCl NaOH ? NaCl H2O
strong
strong
neutral
HC2H3O2 NaOH ? NaC2H3O2 H2O
weak
strong
basic

• Salts can be neutral, acidic, or basic.

• Neutralization does not mean pH 7.

Courtesy Christy Johannesson www.nisd.net/communic
ationsarts/pages/chem
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Salts
NaCl
Salts - Ionic compounds containing a positive ion
other than the hydrogen ion and a
negative ion other than the hydroxide
ion. i.e., a metal and a non-metal
Formulas and names of common salts Formulas and names of common salts Formulas and names of common salts
SALT FORMULA Common Name
sodium chloride NaCl (table) salt
sodium nitrate NaNO3 Chile saltpeter
sodium bicarbonate NaHCO3 baking soda
potassium carbonate K2CO3 potash
ammonium chloride NH4Cl sal ammoniac
Under what conditions do salts conduct current?
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Salt Formation
strong base
strong acid
HCl
NaOH
salt of a strong base and a strong acid
Na
Cl
NaOH HCl ? NaCl H2O
strong base
weak acid
HC2H3O2
NaOH
salt of a strong base and a weak acid
Na
C2H3O2
NaOH HC2H3O2 ? NaC2H3O2 H2O
Note that in each case H-OH (water) is formed
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Salt Formation
weak base
strong acid
H2SO4
NH3
salt of a weak base and a strong acid
(NH4) 2
SO4
H2SO4
NH4OH
NH4OH H2SO4 ? (NH4)2SO4 H2O
weak base
weak acid
HC2H3O2
NH3
NH4OH
salt of a weak base and a weak acid
NH4
C2H3O2
NH4OH HC2H3O2 ? NH4C2H3O2 H2O
Note that in each case H-OH (water) is also
formed
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H2SO4
NH4OH
weak base
strong acid
H2SO4
NH3
salt of a weak base and a strong acid
(NH4) 2
SO4
2 NH4OH H2SO4
(NH4)2SO4 2 HOH
water
ammonium sulfate
sulfuric acid
hydroxide ion
ammonium ion
sulfate ion
1-
1
2-
1
1-
2 NH4OH H2SO4
(NH4)2SO4 2 H2O
NH4
OH-
HOH
H2SO4
(NH4)2SO4
OH-
NH4
HOH
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Reactions that produce salt
acid base
salt water
H3PO4
NH4OH
(NH4)3PO4
H2O


phosphoric acid
ammonium hydroxide
ammonium phosphate
yields
and
water
and
H2O
HNO3
Mg(OH)2
Mg(NO3)2
nitric acid
magnesium hydroxide
magnesium nitrate
K2CO3
H2O
H2CO3
KOH
potassium carbonate
carbonic acid
potassium hydroxide
HC2H3O2
Al(OH)3
Al(C2H3O2)3
H2O
acetic acid
aluminum hydroxide
aluminum acetate
HClO4
Ba(OH)2
Ba(ClO4)2
H2O
perchloric acid
barium hydroxide
barium perchlorate