Transcript Ch. 14 - Liquids

Ch. 15 & 16 - Acids & Bases
III. Titration
(p. 493 - 503)
C. Johannesson
A. Neutralization
 Chemical
reaction between an acid
and a base.
LPChem:Wz
A. Neutralization
 Chemical
reaction between an acid
and a base.
 Products are a salt (ionic compound)
and water.
LPChem:Wz
A. Neutralization
ACID + BASE  SALT + WATER
HCl + NaOH  NaCl + H2O
strong
acid
strong
base
neutral
salt
• Neutralization does not always mean
pH = 7.
• Salts can be neutral, acidic, or basic!
C. Johannesson
A. Neutralization
ACID + BASE  SALT + WATER
HCl + CuOH  CuCl + H2O
strong
acid
weak
base
acidic
salt
HC2H3O2 + NaOH  NaC2H3O2 + H2O
weak
acid
strong
base
C. Johannesson
basic
salt
A. Neutralization
ACID + BASE  SALT + WATER
Strong + Strong  Neutral + water
Acid
Base
Salt
.
Strong + Weak  Acidic + water
Acid
Base
Salt
.
Weak + Strong  Basic + water
Acid
Base
LPChem:Wz
Salt
.
B. Titration
standard solution
 Titration
• Analytical method
in which a standard
solution is used to
determine the
concentration of an
unknown solution.
unknown solution
C. Johannesson
B. Titration
 Equivalence
point
 Point at which equal amounts
of H3O+ and OH- have been
added.
 (moles H3O+ = moles OH-)
• Mathematically determined
by…
• Rapid pH change
LPChem:Wz
B. Titration
 End
Point
 Visual end of titration
• indicator color change
• Should be very similar to
equivalence point.
C. Johannesson
B. Titration
 Strong Acid
& Strong Base = Neutral Salt
 Titration equivalence is at pH = 7
LPChem:Wz
B. Titration
 Strong Acid
& Weak Base = Acidic Salt
 Titration equivalence at pH < 7
On your
homework
today, do #3
like this.
LPChem:Wz
B. Titration
 Weak Acid
& Strong Base = Basic Salt
 Titration equivalence at pH > 7
LPChem:Wz
B. Titration
+
O
moles H3 = moles
MVn = MVn
M: Molarity
V: volume
n: # of H+ ions in the acid
or OH- ions in the base
C. Johannesson
OH
B. Titration
 10.0
mL of 2.3M LiOH are required to
neutralize 20.0 mL of HNO2. Find the
molarity of HNO2.
OH-
H3O+
M = 2.3M
M=?
V = 10.0 mL
n=1
V = 20.0 mL
n=1
LPChem:Wz
MV# = MV#
(2.3M)(10.0mL)(1) =
M(20.0mL)(1)
M = 1.15M HNO2
B. Titration
 42.5
mL of 1.3M KOH are required to
neutralize 50.0 mL of H2SO4. Find the
molarity of H2SO4.
OH-
H3O+
M = 1.3M
M=?
V = 42.5 mL
n=1
V = 50.0 mL
n=2
MV# = MV#
(1.3M)(42.5mL)(1)
=M(50.0mL)(2)
C. Johannesson
M = 0.55M H2SO4