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1) Which will have the greatest affect on the colligative properties of a solution?
1) BeO 2) C6H12O6 3) Ca3N2 4) K2S
2) Which are electrolytes?
a) CoCl2b) CH4
c) C12H22O11
d) HBr
3) Compare and contrast solubility with the rate of solution. How are each affected?
WARM UP
ACIDS AND BASES
• Definition: aqueous solution of Hydrogen
containing compounds
Name the following:
HCl H2SO4 H2SO3 H2S
ACID
• Many contain the polyatomic ion OH- (hydroxide)
Name the following bases:
NaOH Ca(OH)2 Cu(OH)2 NH4OH
BASE
PROPERTIES OF ACIDS
• Ionize in water H3O+
• Corrosive to metals and skin. (React with most metals to form hydrogen gas.)
• Taste sour (like lemons)
• Frequently feel "sticky"
• pH less than 7.
• Neutralizes bases producing salt and water.
• Electrolytes.
• Acids effect indicators:1. Acids turn blue litmus to red
2. Acids turn bromothymol blue to yellow
3. Phenolthalein turns clear/cloudy
PROPERTIES OF BASES
• Ionize in water OH-
• Feel "slippery".
• Taste bitter (like soap)
• Electrolytes
• pH greater than 7.
• Neutralizes acids producing a salt and water.
• Bases effect indicators:
1. Bases turn red litmus to blue
2. Bases turn bromothymol blue to blue
3. Bases turn phenolphthalein to hot pink
ACIDS AND BASES ARE ELECTROLYTES!
• Ionization equation for HBr:
• Ionization equation for NH3:
• Concentration: amount of acid or base ÷ amount
of water or solution
• Strength: how well that particular acid or base
ionizes (amount of H3O+ or OH- )
• Strong acid/base: an acid/base that ionizes almost
completely
• Weak acid/base: an acid/base that only slightly
ionizes
STRENGTH VS. CONCENTRATION
WARM UP TURN IN YOUR LAB
1) Is it an acid or a base?
a) pH=3 b) HNO3 c) tastes bitter d)Ca(OH)2
2) Can an acid be both weak and concentrated? Explain (HINT HINT THIS IS IMPORTANT )
3) How many liters will it take to make a 0.25 M
solution of CaBr2 if you have 0.25 grams of solute?
Strong Weak
HCl H2SO4 HF H2SO3
HBr HClO3 H2S H3PO4
HI HClO4 HNO2
HNO3
LIST OF STRONG AND WEAK ACIDS
Organic acids: end in –COOH, weak
acidEx: vinegar CH3COOH
LIST OF STRONG AND WEAK BASES
Strong Weak
Group I and II
metals with
hydroxides
NH3 and any non-
group I or II
hydroxide
• Strong bases completely dissociates and are
strong electrolytes
• Weak bases only dissociate partially and are
weak electrolytes
KOH – Strong Base
KOH(s)K+(aq) + OH-
(aq)
Cu(OH)2 – Weak Base
Cu(OH)2(aq)↔ Cu2+(aq) + 2OH-
(aq)
Theory Acid
Definition
Base Definition
Arrhenius Releases H+
into solution
Releases OH-
into solution
Bronsted-
Lowery
Proton (H+)
donor
Proton (H+)
acceptor
ACID AND BASE THEORIES
Neutralization, producing a salt and water
General neutralization reaction:
Salt: Ionic compound from the cation of a base and
the anion of an acid
WHAT HAPPENS WHEN YOU MIX AN ARRHENIUS ACID WITH AN ARRHENIUS
BASE?
WaterSaltBaseAcid
COMPLETE AND NET IONIC EQUATIONS!
• LiOH(aq) + HBr(aq) LiBr(aq) + H2O(l)
1. Sodium hydroxide and hydrochloric acid
2. Calcium hydroxide and sulfuric acid
3. Potassium hydroxide and nitric acid
NAME THE SALT PRODUCED AND WRITE THE BALANCED REACTION:
BRONSTED-LOWERY ACID AND BASE
• HCl +NH3 NH4+ + Cl-
• H2O(l) + NH3(aq) ↔ NH4+
(aq) + OH-(aq)
• Monoprotic acid: only has one ionizable hydrogen
ex: HCl, HBr, HC2H3O2, HNO3
• Polyprotic acid: more than one ionizable hydrogen
ex: H2SO4, H3PO4
• Amphoteric: substance that can act as an acid or
as a base
ex: H2O
DEFINITIONS
WATER AS AN ACID OR BASE
Base
H2SO4(aq) + H2O(l) H3O+
(aq) + HSO4-(aq)
Acid
NH3(aq) + H2O(l) ↔ NH4+
(aq) + OH-(aq)
WARM-UP
• Write the complete and net ionic equations for the
neutralization of sulfuric acid and sodium hydroxide
• Compare and contrast Arrhenius and Bronsted-
Lowery acids/bases. Be sure to give an example of
each.
B-L CONJUGATE ACIDS AND BASES
• Conjugate acid: The species that is formed when a
B-L (Bronsted-Lowery) base gains a proton
• Conjugate base: The species that remains after a B-
L acid has given up a proton
IDENTIFY THE CONJUGATES
• NH3 + H3O+ NH4
+ + H2O
• CH3OH + NH2- CH3O
- + NH3
TRY THESE!
• OH- + H3O+ H2O + H2O
• H2O + NH2- OH- + NH3
WRITE THE CONJUGATE BASE
•H3O+
•H2SO4
•HCO3-
•HOCl
•NH4+
WRITE THE CONJUGATE ACID
•I-
•SO32-
•PO43-
•C2H3O2-
•H2BO3-
STRENGTH OF CONJUGATES
•The stronger an acid is, the
weaker its conjugate base; the
stronger a base is, the weaker
its conjugate acid.
• Pure water ionize slightly according to:
The product of molar concentrations of the ions is
equal to a constant Kw.
Kw = 1 * 10-14
IONIZATION OF WATER
OHOHOHOH 322
][][ 3
OHOH
In a neutral solution:
In an acidic solution:
In a basic solution:
RELATIONSHIPS
7
3 10*1][][ OHOH
][][ 3
OHOH
][][ 3
OHOH
pH and pOH
[H+] M [OH-] M pH value
Acidic >1.0x10-7 <1.0X10-7 <7.00
Neutral =1.0x10-7 =1.0x10-7 =7.00
Basic <1.0x10-7 >1.0x10-7 >7.00
• A change in [H+] by a factor of 10 causes the pH to change by 1.
• Solution with a pH of 6 has 10x the [H+] as a solution with a pH
of 7.
pH: measure of [H3O+] in a solution, measure of
“acidity”
pOH: measure of [OH-] in a solution, measure of
“basicity”
PH AND POH
Neutral
0 7 14
Acid Base
Neutral
0 7 14
Base Acid
ACID BASE INDICATORS
1 4
2 5
3 6
IMPORTANT FORMULAS
]log[ 3
OHpH ]log[ 1 OHpOH
pHOH 10][ 3pOHOH 10][ 1
14 pOHpH ]][[ 3
OHOHKW
[H3O+] =
FIND THE PH OF THE FOLLOWING:
a. 1.00 * 10-3 M d. 7.01 * 10-6 M
b. 1.00 * 10-6 M e. 9.47 * 10-8 M
c. 6.59 * 10-10 M f. 6.89 * 10-14 M
a. d.
b. e.
c. f.
• Warm UP!
• 1) how many valence electrons are in the element aluminum?
• 2) what is the pH for the following examples
• a) [H+]= 5.6 x 10-3 M
• b) pOH= 2.11
• 3) use the solubility curve in your hw packet to answer these questions:
a) How many grams of KI can be dissolved in 300 grams of water at 10°C?
a) What type of solution do you have if you dissolve 50 grams of NaCl and 40°C in 100 grams of water?
pH =
FIND THE [H3O+]
a. 3.000 d. 2.523
b. 10.000 e. 6.149
c. 6.61 f. 7.662
a. d.
b. e.
c. f.
pOH =
FIND THE PH FOR THE FOLLOWING:
a. 2 d. 4.98
b. 7 e. 9.71
c. 1.26 f. 3.04
a. d.
b. e.
c. f.
[OH-] =
FIND THE PH FOR THE FOLLOWING:
a. 1.00 * 10-11 M d. 3.45 * 10-8 M
b. 1.00 * 10-6 M e. 4.97 * 10-10 M
c. 2.64 * 10-13 M f. 2.93 * 10-2 M
a. d.
b. e.
c. f.
FIND THE [H3O+]
a. 1.00 * 10-11 M d. 3.45 * 10-8 M
b. 1.00 * 10-6 M e. 4.97 * 10-10 M
c. 2.64 * 10-13 M f. 2.93 * 10-2 M
a. d.
b. e.
c. f.
[OH-] =
WARM-UP
• Find the pH if [H+] is 2.97 x 10-4 M
• Find the [OH-] if the pOH is 6.12
• Find the pOH if [H+] is 8.21 x 10-10 M
• Find the [OH-] if [H+] is 1.26 x 10-2 M
PH CONTINUED
• Find the pH of the following:
• 0.01 M HNO3
• 0.05 M KOH
• 3.0 M HF (8.1% dissociation)
TITRATION INTRO
• Go to page 497 and read to page 502.
• Summarize each section.
• Write the definitions in your own words
• Pages 500 and 501 talk about titration procedures
and techniques. You will be doing this on Tuesday!
• Write the procedure for titrations in your own words
WARM-UP
• What is the conjugate acid for H2O?
• What is the conjugate base of HNO2?
• What is the acid and base that
neutralize to make CaSO4?
• What is an indicator? Give examples
with colors.
BUFFERED SOLUTION
• A solution that can resist changes in pH
• Made up of a weak acid and its
conjugate base
TITRATIONS
• An acid-base titration is a neutralization reaction
that is performed in the lab in order to determine an
unknown concentration of acid or base.
• The moles of acid will equal the moles of base at
the equivalence point.
• Remember this: nBMAVA= naMBVB
M molarity (M)
V volume (V)
• n moles (mol) (coefficients in balanced
reactions)
TITRATIONS
• Endpoint: When you actually stop doing the
titration. This is determined by a color change in the
indicator or an indication from a pH probe.
• Equivalence point: When the solution is neutralized.
• Indicator: weak acid or base; whose color
changes in different pH’s (because the
conjugate base/acid is a different color)
• Standard solution: solution of known
concentration used as the titrant
TITRATION TERMS
TITRATION CURVES
On the following slide you you will see 3 different
curves.
The relationships are:
Strong Acid titrated with Strong Base
Weak Acid titrated with Strong Base
Strong Acid titrated with Weak Base
Using those graphs compare the pH values of each
substance as well as the equivalence points
MORE TITRATION CURVES
Strong base
and weak
acid curve
Strong acid
and weak
base curve
Strong acid
and strong
base curve
MORE CURVES
DIPROTIC ACID CURVE
TITRATIONS
1) If it takes 54mL of 0.1M NaOH to neutralize 125mL
of an HCl solution, what is the concentration of the
HCl?
2) If it takes 25mL of 0.05M HCl to neutralize 345mL of
NaOH solution, what is the concentration of NaOH
solution?
If 26.4 mL of LiOH solution are required to neutralize
21.7 mL of 0.5M HBr, what is the concentration of
the basic solution?
PRACTICE PROBLEM 3
COMMON ACIDS!
• Go to pages 456 and 457.
• Read about each of the acids and
their common uses.
• Summarize the uses for each acid
• Be sure to know this for your test! (and life )