Title: Acids and Bases
1Acids and Bases
2ACIDS
BASES
- electrolytes ?electrolytes
- Produces H30 in water ?produces OH- in water
- react with metals to form H2 gas
- ammonia, antacid, baking soda
- vinegar, soda, apples, citrus fruits
3Acids
- Arrhenius - In aqueous solution
- Acids form hydronium ions (H3O)
HCl H2O ? H3O Cl
acid
4Base
- Arrhenius - In aqueous solution
- Bases form hydroxide ions (OH-)
NH3 H2O ? NH4 OH-
base
5Bronsted-Lowry Acids
- Acids are proton (H) donors
- Bases are proton (H) acceptors
- HCl H2O H3O Cl-
- donor acceptor
-
6NH3, A Bronsted-Lowry Base
- When NH3 reacts with water, most of the
reactants remain dissolved as molecules, but a
few NH3 reacts with water to form NH4 and
hydroxide ion. -
-
- NH3 H2O NH4(aq) OH-
(aq) - acceptor donor
-
7Acid, Base Definitions
8Learning Check AB1
- Describe the solution in each of the following
as 1) acid 2) base or 3)neutral. - A. ___soda
- B. ___soap
- C. ___ wine
- D. ___ water
- E. ___ grapefruit
1
2
1
3
1
9Learning Check
- Identify each as characteristic of an
- A) acid or B) base
- ____ 1. Sour taste
- ____ 2. Produces OH- in aqueous solutions
- ____ 3. Chalky taste
- ____ 4. Is an electrolyte
- ____ 5. Produces H in aqueous solutions
A
B
B
Both
A
1015.1 Acids Generate Hydronium Ions
- Strong Acids completely ionizes in water
- HNO3 H2O ? H3O NO3-
- Weak Acids partially ionizes in water
- HOCl H2O ? H3O ClO-
- Strong Acids MEMORIZE
- If it is not a strong acid then it is a weak
acid!! - HCl H2SO4 HNO3
- HBr HI HClO4
hydrochloric
sulfuric
nitric
hydroiodic
perchloric
hydrobromic
11strong acid vs. weak acid
12Bases Generate Hydroxide Ions
- Strong bases ionizes completely in water
- NaOH ? Na OH-
- Weak bases releases few hydroxide in water
- NH3 H2O ? NH4 OH-
- Strong Bases Memorize
- LiOH NaOH KOH
- Ca(OH)2 Ba(OH)2 Sr(OH)2
- If it is not a strong base then it is a weak
base!!
Lithium hydroxide
Sodium hydroxide
Potassium hydroxide
Calcium hydroxide
Barium hydroxide
Strontium hydroxide
13Learning Check SW1
- Identify each of the following as a 1) strong
acid or base 2) weak acid 3) weak base - A. ___ HCl (aq)
- B. ___ NH3(aq)
- C. ___ NaOH (aq)
- D. ___ H2CO3 (aq)
1
3
1
2
14Acid, Base Conjugates
- Acids are proton (H) donors.
- Bases are proton (H) acceptors.
- Conjugate acid base pair The pair of acid and
base that differ by a H. - Acid- conjugate base base- conjugate acid
HCl H2O ? Cl H3O
base
acid
15Bronsted-Lowry Acids and Bases
- Acid Substance that donate a proton (H)
- Base Substance that accept a proton (H)
- Acid Base reaction H is transferred from the
acid to the base. - Ex.
-
- Conjugate acid base pair The pair of acid and
base that differ by a H. Ex. ACID \ BASE
?
HX
Y
HY
X
Acid
Base
F
HF
Conjugate Acid add H
NO2
HNO2
C2H3O2
HC2H3O2
Conjugate Base subtract H
Memorize NH3 Base
Memorize NH4 Acid
16- Amphoteric substance Substance that can either
donate or accept a hydrogen ion. - Ex. H2O
-
- Example Label the acids and bases, draw lines
to connect the conjugate pairs. - (1) NH3 H2O ? NH4 OH- (2) HF H2O
? F- H3O -
H
H
H2O
?
?
HSO4
HCO3
Acid
Base
Acid
Base
17- Categorize each of the following as an Acid,
Base, or Amphoteric and below each, write the
conjugate acid or base. - H2SO4 H2PO4- NH3 NO2- HSO4-
Acid
Ampho
base
Base
Ampho
HSO4
H3PO4
NH4
HNO2
H2SO4
HPO42
SO42
1815.2 Acidity and Bascitiy and pH
- Water is both an acid and a base.
acid
base
C.A
C.B
- In pure water, the two ions must share the same
concentration. - Experiments show that this concentration is1.00
10-7 M at 25C. - H3O OH- 1.00 10-7 M
19Acidity and Bascitiy
- The concentration of hydronium ions in a solution
expresses its acidity. - The concentration of hydroxide ions in a solution
expresses its basicity.
- When the concentration of H3O goes up, the
concentration of OH- goes down, and vice versa.
20Water dissociation constant
OH (aq)
H2O(l) H2O (l)
?
H3O (aq)
Base
Acid
Keq H3OOH
Equilibrium constant
Kw H3OOH
Water dissociation constant
H3O OH- 1.00 10-7 M
Kw H3OOH 1 x 10 -14
In impure water (contains an acidic or basic
substance) If H3O gt 1.0 x 10-7 M, solution
is acidic. If H3O lt 1.0 x 10-7 M, solution
is basic If H3O 1.0 x 10-7 M, solution is
neutral.
21- A.The OH- when H3O of 1 x 10- 4 M 1) 1 x
10-6 M 2) 1 x 10-8 M 3) 1 x
10-10 M - 3) 1 x 10-10 M
- B.The H3O when OH- of 5 x 10-9 M 1) 1 x
10- 6 M 2) 2 x 10- 6 M 3) 2 x
10-7 M - 2) 2 x 10- 6 M
22What is OH- in a 3.00 10-5 M solution of HCl?
3.00x10-5M
3.00x10-5M
H3O 3.00 10-5 M Kw H3OOH- 1.00
10-14
23pH
- How Acidic Is an Acid?
- power of hydronium ion (pH) measure of the
hydronium ion concentration in a solution - 7
- less than 7 is acidic neutral greater than 7
is basic - Each unit of pH represents 10
- Ex. The difference between 3 and 5 is 100 times
24pH and pOH
- H3O OH- Kw 1 x 10-14
- pH -log H3O pOH -log OH-
- pH pOH 14 10-pH H3O
- pH lt 7 acidic 10 pOH OH-
- pH gt 7 basic
- pH neutral
25Learning Check pH4
- A. The H3O of tomato juice is 1 x 10-4 M.
- What is the pH of the solution?
- 1) - 4 2) 4 3) 8
- B. The OH- of an ammonia solution is
- 1 x 10-3 M. What is the pH of the solution?
- 1) 3 2) 11 3) -11
26Solution pH4
- A. pH - log 1 x 10-4 4
- B. OH- 1 x 10-3
- H3O 1 x 10-11
- pH - log 1 x 10- 11 11
27Learning Check pH5
- The pH of a soap is 10. What is the H3O of
the soap solution? - 1) 1 x 10-4 M 2) 1 x 1010 M 3) 1 x 10-10 M
- H3O 10-pH M 10-10 M
- Acidic or Basic? . . .
- Basic
28Learning Check pH6
- A soap solution has a H3O 2 x 10-8 M. What
is the pH of the solution? 1) 8 - 2) 7.7
- 3) 6
Steps . . .
29Solution pH6
- A soap solution has a H3O 2.0 x 10-8 M.
What is the pH of the solution? - pH -log H3O so . . .
- B) /- LOG 2.0 EE /- 8 7.7
- Acidic or Basic? . . .
- Basic
30Learning Check pH7
- Identify each solution as 1. acidic 2.
basic 3. neutral - A. _____ HCl with a pH 1.5
- B. _____ Pancreatic fluid H 1 x 10-8 M
- C. _____ Sprite soft drink pH 3.0
- D. _____ pH 7.0
- E. _____ OH- 3 x 10-10 M
- F. _____ H 5 x 10-12
1
2
1
3
1
2
31pH on the Calculator
- H3O is 4.5 x 10-6 M
-
- pH /- LOG 4.5 EXP(or EE) /- 6 ENTER
- 5.35
32- Given H3O1 3.02 x 10-8 and pOH 6.48,
- both just calculated, what is OH1-?
- OH- 10-pOH ? . . .
- 2nd log 6.48 3.31 x 10-7
- Can also do by Kw H3O1OH1-
- OH- 1.0 x 10-14/3.02 x 10-8 . . .?
- 1 EE 14 3.02 EE 8
- 3.31 x 10-7
33Neutralization
- Neutralization Reactions
- Strong acids and strong bases react to form a
salt and water - HCl NaOH ? _____ _____
- Depends on the strength and amount of acids and
bases used - Neutralization does not mean pH 7.
- When acid and bases with equal amounts of
hydrogen ion H and hydroxide ions OH- are mixed,
the resulting solution is neutral.
NaCl H2O
34Ionic Equations for Neutralization
- HCl NaOH HOH NaCl
- Write strong acids, bases soluble salts as ions
- H Cl- Na OH- Na Cl- H2O
- Cross out matched ions
- H Cl- Na OH- Na Cl- H2O
- Write a net ionic reaction
- H OH- H2O
35- Equal volumes of 1 molar hydrochloric acid
- (HCl) and 1 molar sodium hydroxide base
- (NaOH) are mixed. After mixing, the
- solution will be
- A strongly acidic.
- B weakly acidic.
- C nearly neutral.
- D weakly basic.