CP NT Ch 19: Acid and Bases—An Introduction
Properties of Acids
1. _________________________ taste
2. Can produce H+ (________________) ions (____________________)
3. Change the color of litmus from _____________________ to ____________________
4. Reacts with ________________________ such as Zn and Mg to produce ________________ gas.
 Ba(s) + H2SO4  BaSO4(aq) + H2(g)
5. Reacts with ___________________________ (CO32-) to produce CO2
 NaHCO3(s) + CH3COOH(aq)  NaCH3COO(aq) + H2O(l) + CO2(g)
6. Acids conduct an ________________________ current
Properties of Bases
1. _________________________ or caustic taste
2. A _________________________, soapy feeling
3. Can produce OH- (_________________________) ions
4. Ability to change litmus from __________________ to _____________________
5. Bases ___________________________ an electric current
6. Bases react with acids to produce a salt and water. This is known as a ________________________ reaction.
 HCl + NaOH  NaCl + H2O
 HCl + Mg(OH)2  MgCl2 + H2O
acid
base
salt
water
Ions in Solution
 _______________________ solutions contains more hydrogen (H+) ions than hydroxide ions (OH-) pH < 7
 _______________________ solutions contains more hydroxide ions (OH-) than hydrogen ions pH > 7
 _______________________solutions contain an equal concentration of hydrogen and hydroxide ions pH = 7
Three Definitions of Acids/Bases
Type
Acid
Arrhenius
Bronsted-Lowry
Lewis
Base
Bronsted-Lowry Conjugate Acid/Base Pairs
 HX(aq) + H2O(l)  H3O+(aq) + X-(aq)
acid
base
Conjugate
Conjugate
Acid
Base
Problems with it
NH3(aq) + H2O(l)  NH4+ (aq) + OH-(aq)
base
acid
conjugate conjugate
acid
base

______________________ acid is the substance produced when a base ________________ a hydrogen ion from
an acid
 Conjugate ________________ is the substance that the acid _________________________ a hydrogen ion to
form a base
 Conjugate acid-base pair consists of two substances related to each other by donating and accepting of a
___________________________hydrogen ion
Practice: Conjugate Acid and Conjugate Base
 HCO3- + H2S  H2CO3 + HS
H2PO4- + OH-  HPO42- + H2O

H2SO4 + NH3  HSO4- + NH4+

HC2H3O2 + H2O  H3O+ + C2H3O2-
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Water in Acid/Base solutions
 Water and other substances can act as ________________ acids and bases and are said to be
_________________________.

Hydronium ion = H3O+ = H+ (Remember H+ is a ___________________________)

H2O(l) + H2O(l) ⇆ H3O+(aq) + OH-(aq)
Monoprotic and Polyprotic Acids
 __________________________ acid donates __________________ hydrogen ion

________________________ acid donates __________________ than one hydrogen ion
Strengths of Acids and Bases
Electrical Conductivity
 Acidic and basic solutions ______________________ electricity.
Strengths of Acids
 Acids that completely ionize (____________________) are called strong acids.
o Strong acids produce a ______________________________electric current = strong
__________________________
o HCl(aq) +H2O(l)  H3O+(aq) + Cl-(aq)
 ________________________ acids ___________________________ ionize in solutions = weak ______________
o Produce fewer ions and cannot conduct electricity as efficiently as strong acids
o HC2H3O2(aq) +H2O(l)  H3O+(aq) + C2H3O2-(aq)
Strength of Bases
 Strong bases dissociate ______________________ into metal ions and ______________________ ions.
 Weak bases ionizes only _________________________________ in dilute aqueous solution
Six Strong Acids
 Hydrochloric acid: _____________________
 Hydrobromic acid: _____________________
 Hydroiodic acid: _____________________
 Sulfuric acid:
_____________________
 Nitric acid:
_____________________
 Perchloric acid: _____________________
Eight Strong Bases
 Lithium hydroxide: ____________________
 Sodium hydroxide: _____________________
 Potassium hydroxide: _____________________
 Rubidium hydroxide: _____________________
 Cesium hydroxide:
____________________
 Calcium hydroxide: ______________________
 Strontium hydroxide: _____________________
 Barium hydroxide: ______________________
Acid/Base Strength vs. Concentration
 Do not get acid/base strength confused with ___________________________.
 Acid/base strength is based on the ability to _________________________.
 Concentration is based on how much is ______________________ in solution.
 You can have a strong dilute acid – the acid ___________________ dissociates, but there is not much acid
dissolved in _______________________.
Acid Ionization Constant
 Acid _________________________ constant (_________________) is the value of the equilibrium constant
expression(Keq) for the ionization of a weak acid.
 ___________________________ Ka _____________________acid
 ___________________________ Ka ______________________acid
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Base Ionization Constant
 The ______________________ ionization ________________________ (Kb) is the value of the equilibrium
constant expression (Keq) for the ionization of a base
 _____________________ Kb strong base
 ________________________ Kb weak base
Write the ionization equation and acid ionization
constant (Ka) expressions for the acid HF
Write the ionization equation and base ionization
constant (Kb) expressions for the base NH3
What is pH?
H2O(l)  H+(aq) + OH-(aq)
Keq = Kw =
The ion product constant for water (Kw) is the equilibrium constant (Keq) expression for the self-ionization of
water. The value is dependent upon temperature
Kw = __________________________ at 298 K
From this you can calculate the hydrogen ion concentration or the hydroxide ion concentration.
At 298 K the H+ ion concentration of an aqueous solution is 1.0 x 10-5. What is the OH- ion concentration in the
solution? Is the solution acidic, basic, or neutral?
At 298 K the H+ ion concentration of an aqueous solution is 2.5 x 10-6. What is the OH- ion concentration in the
solution? Is the solution acidic, basic, or neutral?
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pH =
The pH scale
pH < 7 acidic
pH = 7 neutral
pH > 7 basic (alkaline)
Calculating pH
What is the pH of a solution with a concentration of 1.0 x 10-6 hydrogen ions.
What is the pH of a solution if the concentration of the hydroxide ions is 9.6 x 10-4 M
pOH =
Ammonia gas has a hydroxide-ion concentration of 4.0 x10-3 M. Calculate the pOH and pH at 298 K
A solution contains a hydrogen ion concentration of 3.56 x 10-8 M. Calculate the pH and pOH at 298 K.
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Calculating Ion Concentration from pH
[H+] =
[OH-] =
What are [H+] and [OH-] in a healthy person’s blood that has a pH of 7.40? Assume that the temperature is 298 K.
What are [H+] and [OH-] at a pH of 2.3?
What are [H+] and [OH-] at a pH of 5.54?
Neutralization Reactions



A reaction in which an ___________ and a _________________ react to produce a _____________ and
_____________
A ____________ is an ionic compound made up of a _______________ and a _____________
Example:
o HCl(aq) + NaOH(aq) →
o
Mg(OH)2(aq) + HCl(aq) →
o
HNO3(aq) + NaOH(aq) →
o
Ba(OH)2(aq) + HCl →
o
H2SO4(aq) + CsOH →
o
HNO3 + KOH →
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Titrations








Purpose—to find the unknown _________________ of a solution
Procedure—add a solution with ___________ concentration to a solution of _____________ concentration
Burette—a piece of _______________ used for dispensing accurate volumes of a solution
o the solution of _____________ concentration goes in the burette
Analyte (unknown solution)—the solution that is being ___________________
Titrant (standard solution)—the solution of ____________ concentration that is __________ to the analyte
Equivalence point—when the acid and base are mixed and the number of hydrogen ions _____________
the number of hydroxide ions; [H+] = [OH−]
Acid-Base indicator—a chemical dye whose colors are affected by ____________ and ___________
solutions
o _______________________ is a common acid-base indicator
End point—the point at which the indicator used in a titration ______________ color
Calculations
Example 1:
HC2H3O2 + NaOH → H2O + NaC2H3O2
In a titration, the volume of base needed was 9.50 mL of 0.500 M NaOH to reach the equivalence
point. The volume of HC2H3O2 was 5.89 mL. Find the molarity of the acid.
Example 2:
In a titration, 43.21 mL of a 0.03020 M RbOH solution is required to exactly neutralize 30.00
mL of a H2SO4 solution. What is the molarity of the H2SO4 acid solution? (Hint: First write the neutralization
equation)
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