Chapter 13
Properties of Liquids
Liquid water
provides the base for
the recreation of
windsurfing and also
for our bodies.,
Water is a unique
liquid on our blue
planet.
Foundations of College Chemistry, 13e
John Wiley & Sons, Inc
Morris Hein and Susan Arena
Chapter Outline
13.1 What is a Liquid?
13.2 Evaporation
13.3 Vapor Pressure
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What Is a Liquid?
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Evaporation
Evaporation or vaporization is the escape of molecules
from the liquid state to the gas or vapor state.
liquid  vapor
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Sublimation
Sublimation is the phase change from the solid state to
the gas or vapor state without going through the
liquid state.
solid  vapor
CO2(s)  CO2(g)
I2(s)  I2(g)
Iodine crystals
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Vapor Pressure
In a closed container, an
equilibrium develops
where there are as
many molecules
evaporating as there
are condensing.
Vapor pressure is the
pressure exerted by a
vapor in equilibrium
with its liquid.
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liquid
evaporation
condensation
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13-6
Vapor Pressure
Is independent of the quantity of the liquid or its surface
area
Increases with increasing temperature.
Depends on the strength of the attraction between
molecules in the liquid state.
Volatile liquids have very weak attractive forces and so
evaporate rapidly at room temperature. Volatile
liquids have high vapor pressures at 25°C.
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Vapor Pressure
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13-8
Your Turn!
The vapor pressure of diethyl ether was 318 mm Hg
while the vapor pressure of ethyl alcohol was 44 mm
Hg. Which substance has stronger attractive forces
between molecules?
a. diethyl ether
b. ethyl alcohol
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Your Turn!
In a system at equilibrium between the liquid and gas
phases
a. Particles stop changing phase
b. The rate at which particles change from liquid to gas
exceeds the rate at which they change from gas to
liquid.
c. The rate at which particles change from gas to liquid
equals the rate at which they change from liquid to
gas.
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Your Turn!
Which has the lowest vapor pressure?
a. 100 mL of gasoline at 15°C
b. 25 mL of gasoline at 50°C
c. 50 mL of gasoline at 50°C
d. 25 mL of gasoline at 70°C
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Chapter 14
Solutions
Brass, a solid
solution of zinc and
copper, is used to
make musical
instruments and
many other objects.
Foundations of College Chemistry, 13e
John Wiley & Sons, Inc
Morris Hein and Susan Arena
Chapter Outline
14.1 General Properties of
Solutions
14.5 Solutions: A Reaction
Medium
14.2 Solubility
14.6 Concentration of Solutions
14.3 Factors Related to
Solubility
14.4 Rate of Dissolving Solids
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General Properties of Solutions
A solution is a homogeneous mixture of one or more
solutes and the solvent.
The solute is the substance being dissolved.
The solvent is the dissolving agent and is usually the
most abundant substance in the mixture.
Air is a solution of N2(g), O2(g), Ar(g), CO2(g)...
What substance is the solvent in air?
N2(g), since 78% of air is N2.
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Common Types of Solutions
What gas is the solute in soft drinks?
carbon dioxide
What is another solute in soft drinks?
sugar and
flavorings
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Properties of a True Solution
1. A homogeneous mixture of 2 or more components
whose ratio can be varied.
2. The dissolved solute is molecular or ionic in size
(less than 1 nm).
3. Liquid or gaseous solutions can be colored or
colorless and are usually transparent.
4. The solute will not settle out of the solution.
5. The solute can be separated from the solvent by
physical means.
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Your Turn!
Sweet tea is prepared by dissolving an instant tea packet
in water. Which substance is the solvent?
a. sugar
b. tea
c. water
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Your Turn!
A solution of alcohol and water is prepared by adding
25 mL of water to 75 mL methyl alcohol. Which
substance is the solute?
a. methyl alcohol
b. water
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Solubility
Solubility describes the amount of a
substance that will dissolve in a specified
amount of solvent at a particular
temperature.
For example: 36 g NaCl/100 g H2O at 20°C
Miscible is the term used if 2 liquids will
dissolve in each other.
Immiscible is used if the liquids will not
dissolve in each other.
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Ionic Compound Solubility Rules
NaCl
soluble
AgNO3
soluble
AgCl
insoluble
AgOH
insoluble
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Your Turn!
Use the ionic compound solubility rules to predict the
solubility of barium sulfate.
a. soluble
b. insoluble
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Your Turn!
Use the ionic compound solubility rules to predict the
solubility of ammonium carbonate.
a. soluble
b. insoluble
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Factors Related to Solubility
“Like dissolves like”
Polar compounds dissolve in polar solvents, like water
and alcohol (CH3CH2OH)
– Acetone [(CH3)2CO] dissolves in water because it
has a net dipole on the O to C bond, making it
polar.
Nonpolar compounds dissolve in nonpolar solvents, like
petroleum ether and CCl4
– Hexane [CH3(CH2)4CH3] dissolves in petroleum
ether because they are both nonpolar.
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Ionic Solubility
Many ionic compounds dissolve in
water because they form ion to
dipole forces with water (a
strong intermolecular force).
The ions become surrounded by
water (become hydrated).
The cation is attracted to the
partially negative O in water
The anion is attracted to the
partially positive H in water.
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Temperature and Solubility
Most solids’
solubility increases
with increasing
temperature. (See
red lines.)
All gases solubility
decreases with
increasing
temperature. (See
blue lines.)
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Pressure and Solubility
Pressure does not affect the solubility
of solids or liquids, but there is a
large effect with gases.
The solubility of gas in a liquid is
proportional to the pressure of the
gas over the liquid.
Sodas are canned under high pressure.
When you open a can, the pressure
decreases and bubbles form,
releasing the excess gases.
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Your Turn!
Under what conditions are gases most soluble in
liquids?
a. high temperature, high pressure
b. high temperature, low pressure
c. low temperature, high pressure
d. low temperature, low pressure
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Saturated and Unsaturated Solutions
Saturated solutions contain as much dissolved solute
as the solvent will hold at a given temperature.
Saturated solutions are always in equilibrium with
undissolved solute.
undissolved solute → dissolved solute
Any point on the solubility curve represents a saturated
solution of that solute.
Unsaturated solutions contain less solute than the
amount needed to saturate the solution.
→
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Supersaturated Solutions
Supersaturated solutions
contain more solute than the
amount needed to saturate the
solution at a particular
temperature.
Supersaturated solutions are
unstable – stirring, adding a
crystal of solute – will cause
the excess solute to come out
of solution.
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Your Turn!
What mass of this
compound will dissolve
at 30°C?
a. 5.0 g
b. 5.4 g
c. 5.8 g
d. 6.0 g
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Your Turn!
6.0 g of solute is
dissolved in 100 g of
water at 60°C. The
solution is allowed to
cool to 25°C. No crystals
form. The solution is:
a. saturated
b. unsaturated
c. supersaturated
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Your Turn!
The addition of a crystal sodium acetate to a sodium
acetate solution causes additional crystals of sodium
acetate to precipitate. The original solution was
a. Saturated
b. Supersaturated
c. Unsaturated
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Rate of Dissolving Solids
Particle Size
A solid can dissolve only at the surface that is in
contact with the solvent.
Smaller crystals have a larger surface to volume ratio
than large crystals.
Smaller crystals dissolve faster than larger crystals.
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Surface Area
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Rate of Dissolving Solids
Temperature
Increasing the temperature increases the rate at which
most compounds dissolve.
This occurs because solvent molecules strike the surface
of the solid more frequently, causing the solid to
dissolve more rapidly.
The dissolved solute particles are also carried away
from the solid by the higher kinetic energy solvent
molecules, allowing more solvent to hit the surface.
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Rate of Dissolving Solids
Concentration of solution
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Rate of Dissolving Solids
Agitation or Stirring
Stirring rapidly distributes the dissolved solute
throughout the solution, eliminating the saturated
solution that forms at the surface of the solid.
Moving dissolved solute away from the surface
increases the contact between water molecules and
the solid and increases the rate of dissolving.
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Your Turn!
Which would most likely increase the solubility of a
solid in water?
a. Stirring
b. Grind the solid to increase its surface area
c. Increase the pressure
d. Increase the temperature
e. All of the above
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Solutions: A Reaction Medium
Dissolving reactants allows them to come into solution.
Combining two solids usually will not result in any
significant reaction:
KCl(s) + AgNO3 (s)  no reaction
But if you dissolve those same reactants in water, the
silver ion can collide with the chloride ion, resulting
in solid AgCl.
KCl(aq) + AgNO3(aq)  AgCl(s) + KNO3(aq)
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Concentration of Solutions
Qualitative expressions of concentration:
• A dilute solution contains a relatively small amount
of dissolved solute.
• A concentrated solution contains a relatively large
amount of solute.
Hydrochloric acid is sold as a concentrated 12 M
(moles/ L) solution. A dilute 0.1 M solution is
commonly found in labs.
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Concentration of Solutions
Quantitative expressions of concentration:
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Mass Percent
Calculate the mass % NaCl in a solution prepared by
dissolving 50. g NaCl in 150. g H2O.
Knowns
Solving for
50. g NaCl (solute)
150. g H2O (solvent)
50. g NaCl + 150. g H2O =
200. g mass of solution
mass of solute
mass % =
 100%
mass of solution
50 g NaCl
 100% = 25% NaCl
Calculate mass % 
200 g soln
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Mass Percent
mass solute
 100%
mass solution
Calculate the mass of Na2CO3 and water needed to
make 350. g of a 12.3% solution.
Knowns
350. g solution
12.3% solution
Solving for
mass of solute (Na2CO3) and mass of H2O
Calculate
12.3 g Na 2CO3
350. g soln 
= 43.1 g Na2CO3
100 g soln
mass of H2O = 350. g – 43.1 g = 307 g H2O
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Mass-Volume Percent
g solute
 100%
ml solution
Normal saline is a 0.90 m/v % NaCl solution. What
mass of sodium chloride is needed to make 50. mL of
normal saline?
Knowns
50. mL solution
0.90 m/v% solution
Solving for
mass of solute (NaCl)
0.90 g NaCl
Calculate 50. mL soln 
= 0.45 g NaCl
100 mL soln
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Volume Percent
volume solute
100%
volume solution
What volume of beer that is 6.0 % by volume alcohol
contains 200. ml CH3CH2OH (ethyl alcohol)?
Knowns
200. mL EtOH (solute)
6.0 volume % solution
Solving for
volume of solution = 3.3 L beer
100 mL beer
1L

Calculate 200 mL EtOH 
6.0 ml EtOH 1000 mL
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Your Turn!
A 20.0 % solution of KCl has a mass of 400. g. What
mass of KCl is contained in this solution?
a. 20.0 g
b. 80.0 g
c. 320. g
d. 400. g
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Your Turn!
A solution is prepared by mixing 20.0 mL of propanol
with enough water to produce 400.0 mL of solution.
What is the volume percent of propanol in this
solution?
A. 0.500 %
B. 4.76 %
C. 5.00 %
D. 5.26 %
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Molarity
moles of solute
L of solution
A 1.0 M KCl
solution is
prepared by
dissolving 1.0
moles KCl in
enough water to
make 1.0 L of
solution.
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Molarity
moles of solute
L of solution
Calculate the molarity of a solution prepared by
dissolving 9.35 g KCl in enough H2O to make 250.
mL solution.
9.35 g KCl (solute)
Knowns
250. mL solution
Solving for
moles of solute
M =
= 0.502 M KCl
L of solution
Calculate
9.35 g KCl
1 mol KCl
M=

250 mL soln
74.551 g KCl
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1000 mL

1L
14-49
Dilution
Dilution: Adding solvent to a concentrated solution to
make a more dilute solution.
When you dilute a concentrated solution, only the
volume of solution changes. The quantity of solute
remains the same.
Volume (V) × Molarity (M) = moles of solute
V1 × M1 = V2 × M2
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Dilution V1 × M1 = V2 × M2
How many milliliters of 12 M HCl are needed to make
500. mL of 0.10 M HCl?
Knowns
Solving for
12 M HCl (concentrated solution) M1
0.10 M HCl (dilute solution) C2
500. mL (dilute solution) V2
volume of 12 M HCl V1
Calculate
V2 M 2 500 mL×0.10 M
V1 

= 4.2 mL of 12 M HCl
M1
12 M
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Your Turn!
What is the molarity of a solution in which 5.85 g of
NaCl is dissolved in 200. mL of solution?
a. 0.500 M
b. 1.00 M
c. 2.00 M
d. 4.00 M
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Your Turn!
What is the molarity of the resulting solution when 300.
mL of a 0.400 M solution is diluted to 800. mL?
a. 0.109 M
b. 0.150 M
c. 1.07 M
d. 1.47 M
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Chapter 15
Acids, Bases, and Salts
Lemons and limes are
examples of food which
contains acidic solutions.
Foundations of College Chemistry, 13e
John Wiley & Sons, Inc
Morris Hein and Susan Arena
Chapter Outline
15.1 Acids and Bases
15.8 Ionization of Water
15.2 Reactions of Acids
15.9 Introduction to pH
15.3 Reactions of Bases
15.4 Salts
15.5 Electrolytes and
Nonelectrolytes
15.6 Dissociation and
Ionization of Electrolytes
15.7 Strong and Weak
Electrolytes
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Arrhenius Acids
Definition: An acid solution
contains an excess of H+ ions.
Properties
1. Sour taste
2. Turn blue litmus red
3. The ability to react with
• Metals to produce H2 gas
• Bases to produce salt and water
• Carbonates to produce carbon dioxide
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Arrhenius Bases
Definition: A base solution
contains an excess of OH- ions.
Properties
1. Bitter or caustic taste
2. Turn red litmus blue
3. Slippery, soapy feeling
4. Neutralize acids
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Your Turn!
Which type of solution would have a sour taste and turn
blue litmus red?
a. Acid
b. Base
c. Salt
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Reactions of Acids
Acids react with metals that lie above H in the activity
series:
acid + metal  salt + hydrogen
2HCl(aq) + Mg(s)  MgCl2(aq) + H2(g)
Acids react with bases (neutralization)
acid + base  salt + water
2HCl(aq) + Ca(OH)2(aq) CaCl2(aq) + 2H2O (l)
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Reactions of Acids
Acids react with metal oxides
acid + base  salt + water
2HCl(aq) + Na2O(s)  2NaCl(aq) + H2O(l)
Acids react with metal carbonate
acid + base  salt + water + carbon dioxide
2HCl(aq) + Na2CO3(aq) 2NaCl(aq) + H2O(l) + CO2(g)
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Reactions of Bases
Bases can be amphoteric
as base: Zn(OH)2(aq)+ 2HBr(aq)  ZnBr2(aq) + 2H2O(l)
as acid: Zn(OH)2(aq)+ 2NaOH(aq)  Na2Zn(OH)4(aq)
NaOH and KOH react with metals
base + metal + water  salt + hydrogen
2NaOH(aq) + 2Al(s) + 6H2O(l)  2NaAl(OH)4(aq) + 3H2O(g)
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Your Turn!
What gas is produced by the reaction of sodium
bicarbonate with acetic acid?
a. Hydrogen
b. Carbon dioxide
c. Nitrogen
d. Oxygen
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Salts
Salts are the result of acid-base
neutralization reactions.
HCl(aq)+ NaOH(aq) NaCl(aq)+ H2O(l)
Salts are ionic compounds composed
of a cation (usually a metal or the
ammonium ion) and an anion (not
oxide or hydroxide).
Salts are usually crystals with high
melting and boiling points.
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Your Turn!
What salt forms from the reaction of magnesium
hydroxide and sulfuric acid?
a. MgS
b. Mg2S
c. MgSO4
d. Mg2SO4
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Your Turn!
What salt forms from the reaction of aluminum oxide
and hydrobromic acid?
a. AlBr
b. AlBr3
c. Al2Br
d. Al2Br3
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Electrolytes and Nonelectrolytes
Electrolytes are compounds whose aqueous solutions
conduct electricity.
Nonelectrolytes are substances whose aqueous
solutions are nonconductors.
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Electrolytes and Nonelectrolytes
It is the movement of ions that
conduct electricity in water .
Acids, bases and salts are
electrolytes because they
produce ions in water when they
dissolve.
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Dissociation of Electrolytes
Salts dissociate into cations and anions when they
dissolve in water.
NaCl(s)  Na+(aq) + Cl-(aq)
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Ionization of Electrolytes
Ionization is the formation of ions; it is the result of the
chemical reaction with water.
Acids ionize in water, producing hydronium ions and
anions.
HCl(g) + H2O(l)  H3O+(aq) + Cl-(aq)
H3PO4(aq) + H2O(l) → H3O+(aq) + H2PO4-(aq)
Weak bases ionize in water, producing hydroxide ions
and cations.
NH3(aq) + H2O(l) → OH- (aq) + NH4+(aq)
→
→
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Your Turn!
Which will not dissociate when placed in water?
a. KBr
b. HCl
c. CH3OH
d. HClO4
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Your Turn!
A solution is tested with the conductivity apparatus and
the light bulb did not light. Which of the following is
not likely?
a. The beaker contained only water.
b. The beaker contained water and C6H12O6.
c. The beaker contained water and CaCl2.
d. All of the above are likely possibilities.
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Strong and Weak Electrolytes
Strong electrolytes are
essentially 100% ionized in
water (HCl).
Weak electrolytes are much
less ionized (HC2H3O2).
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Strong and Weak Electrolytes
Use double arrows to indicate weak ionization.
HC2H3O2(aq) + H2O(l) → H3O+(aq) + C2H3O2-(aq)
HF(aq) + H2O(l) → H3O+(aq) + F-(aq)
→
→
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Salts
Salts dissociate into at least 2 ions.
A 1M solution of NaCl produces a 2M solution of ions.
NaCl(s)  Na+(aq) + Cl-(aq)
1 mole 1 mole + 1 mole
A 1M solution of CaCl2 produces a 3M solution of ions.
CaCl2(s)  Ca2+(aq) + 2Cl-(aq)
1 mole 1 mole + 2 mole
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Your Turn!
What is the concentration of chloride ion in a 2.0 M
solution of calcium chloride?
a. 1.0 M
b. 2.0 M
c. 3.0 M
d. 4.0 M
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Ionization of Water
Pure water auto-ionizes
H2O(l) + H2O(l) → H3O+(aq) + OH-(aq)
→
Concentration H3O+ = Concentration OH- = 1×10-7 M
[H3O+]×[OH-] = 10-14
In acid solutions, [H3O+]>[OH-]
In basic solution, [H3O+]<[OH-]
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Introduction to pH
pH = -log[H+]
In pure water, [H+] = 1×10-7 M so
pH = -log(10-7) = 7
high H+
low OH-
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low H+
high OH-
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pH
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Your Turn!
How many times more acidic is a solution with a pH of
3 than a solution with a pH of 5?
a. 2
b. 20
c. 200
d. 100
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C15 Acids, Bases and Salts Copyright 2011
John Wiley & Sons, Inc
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Introduction to pH
pH = -log[H+]
3/23/2016
C15 Acids, Bases and Salts Copyright 2011
John Wiley & Sons, Inc
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Introduction to pH
Calculate the pH of a 0.015M H+ solution.
pH = - log (0.015) = 1.82
Note: The digits to the left of the decimal place in the
pH (the characteristic of the log) reflect the power of
ten in the [H+]. In this case, the 1. The characteristic
is NOT one of the significant figures in the pH.
The number of decimal places for the mantissa of a log
must equal the number of significant figures in the
original number.
3/23/2016
C15 Acids, Bases and Salts Copyright 2011
John Wiley & Sons, Inc
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Your Turn!
What is the pH of a 0.020 M hydrochloric acid solution?
a. 0.020
b. -2.0
c. 1.70
d. 1.7
e. -1.7
3/23/2016
C15 Acids, Bases and Salts Copyright 2011
John Wiley & Sons, Inc
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Your Turn!
What is the pH of a solution of sodium hydroxide that
has a hydronium ion concentration of 2.5×10-11?
a. 11
b. 10.6
c. -10.60
d. 10.60
3/23/2016
C15 Acids, Bases and Salts Copyright 2011
John Wiley & Sons, Inc
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