Title: Acids and Bases
1Chapter 15
215.1 What are Acids and Bases?
- Objectives
- To name acids and bases.
- To write formulas for acids and bases.
3Rules for Naming Acids
- -ide ? hydro_____ic acid
- -ate ? _____ic acid
- -ite ? _____ous acid
- If a compound begins with hydrogen name it as an
acid.
4Examples Naming Acids
- 1. HCl
- The anion is chloride (Cl-)
- For an anion ending in ide ? hydro___ic acid
- Therefore, the name is hydrochloric acid
5Examples Naming Acids
- 1. HCl
- The anion is chloride (Cl-)
- For an anion ending in ide ? hydro___ic acid
- Therefore, the name is hydrochloric acid
- 2. HNO3
- The anion is nitrate (NO3-)
- For an anion ending in ate ? ___ic acid
- Therefore, the name is nitric acid
6Examples Naming Acids
- 1. HCl
- The anion is chloride (Cl-)
- For an anion ending in ide ? hydro___ic acid
- Therefore, the name is hydrochloric acid
- 2. H2SO4
- The anion is sulfate (SO42-)
- For an anion ending in ate ? ___ic acid
- Therefore, the name is sulfuric acid
- 3. H2SO3
- The anion sulfite (SO32-)
- For an anion ending in ite ? ___ous acid
- Therefore, the name acid sulfurous acid
7Name the following compound HBr
- Bromic acid
- Bromous acid
- Hydrobromic acid
- Hydrobromous acid
- None of the above
8Name the following compound HBr
- Bromic acid
- Bromous acid
- Hydrobromic acid
- Hydrobromous acid
- None of the above
9Name the following compound H2C2O4
- Chromic acid
- Oxalate acid
- Dihydrogen dicarbon tetraoxide
- Oxalic acid
- None of the above
10Name the following compound H2C2O4
- Chromic acid
- Oxalate acid
- Dihydrogen dicarbon tetraoxide
- Oxalic acid
- None of the above
11Practice Naming Acids
- 1. H2SO3
- 2. HF
- 3. H3PO4
- 4. HNO3
- 5. HI
12Practice Naming Acids
- 1. H2SO3 sulfurous acid
- 2. HF hyrofluoric acid
- 3. H3PO4 phosphoric acid
- 4. HNO3 nitric acid
- 5. HI hydroiodic acid
13Examples Writing Formulas for Acids
H SO42-
- 1. Sulfuric acid
- The anion is sulfate (SO42-)
- The cation is H
- Criss-cross charges to get H2SO4
- 2. Carbonic acid
- The anion is carbonate (CO32-)
- The cation is H
- Criss-cross charges to get H2CO3
H2SO4
H CO32-
H2CO3
14Practice Writing Formulas for Acids
- 1. Hydrochloric acid
- 2. Nitric acid
- 3. Phosphorous acid
- 4. Hydroiodic acid
15Practice Writing Formulas for Acids
- 1. Hydrochloric acid HCl
- 2. Nitric acid HNO3
- 3. Phosphorous acid H3PO3
- 4. Hydroiodic acid HI
16Acids you should know
Strong Acids Weak Acids
Hydrochloric Acid Phosphoric Acid
Sulfuric Acid Acetic Acid
Nitric Acid
17Some Bases
Strong Bases Weak Bases
Sodium Hydroxide Ammonia
Potassium Hydroxide Sodium Carbonate
Calcium Hydroxide Potassium Carbonate
Barium Hydroxide
Sodium Phosphate
1815.1 What are acids and bases? continued
- Objectives
- To list properties of acids and bases.
- To define acid and base.
- To identify the acid, base, conjugate acid, and
conjugate base in a chemical reaction.
19Properties of Acids
- Taste sour
- Form Hydronium Ions (H3O)
- Conduct electricity
- React with metals
20Properties of Bases
- Taste bitter
- Feel slippery
- Generate Hydroxide Ions (OH-)
21Acid
- Arrhenius Acid any substance that, when added to
water, increases the hydronium ion (H3O)
concentration - Note H and H3O are used
interchangeably
22Base
- Arrhenius Base generates hydroxide ions (OH-)
when dissolved in water
23BrØnsted-LowRY Acid
- A substance that donates a proton (H) to another
substance.
24BrØwnsted-lowry base
- A substance that accepts a proton (H).
25Conjugate Acid and Conjugate Base
- Conjugate Acid an acid that forms when the base
gains a H - Conjugate Base the base that forms when an acid
loses an H
26Identify the conjugate base for the following
acids
Acid Conjugate Base
HCl Cl-
H2SO4
H3O
HSO4-
HOCl
H2PO4-
NH4
27Identify the conjugate base for the following
acids
Acid Conjugate Base
HCl Cl-
H2SO4 HSO4-
H3O H2O
HSO4- SO42-
HOCl OCl-
H2PO4- HPO42-
NH4 NH3
28Identify the conjugate acid for the following
bases
Conjugate Acid Base
NH4 NH3
HCO3-
HS-
Br-
29Identify the conjugate acid for the following
bases
Conjugate Acid Base
NH4 NH3
H2CO3 HCO3-
H2S HS-
HBr Br-
30Identify the acid, base, conjugate acid, and
conjugate base in the following chemical
reactions
- HCl OH- ? Cl- H2O
- acid base c. base c. acid
- 2. HNO3 OH- ? NO3- H2O
- 3. H2O HCO3- ? H2CO3 OH-
31Identify the acid, base, conjugate acid, and
conjugate base in the following chemical
reactions
- HCl OH- ? Cl- H2O
- acid base c. base c. acid
- 2. HNO3 OH- ? NO3- H2O
- acid base c. base c. acid
- 3. H2O HCO3- ? H2CO3 OH-
- acid base c. acid c. base
32Amphoteric Substances
- An amphoteric substance can donate AND accept
protons. - Example HCO3- is amphoteric
- HCO3- NH3 ? CO32- NH4
- Acid Base C. Base C. Acid
- HCO3- H3O ? H2CO3 H2O
- Base Acid C. Acid C. Base
3315.2 Acidity, Basicity, and pH
- Objective
- To calculate the concentration of the hydronium
ion and the hydroxide ion.
34Self-Ionization of Water
- H2O(l) H2O(l) ? H3O(aq) OH-(aq)
- H3O OH- 1.00 x 10-7 M
- What is the Keq for water?
35Self-Ionization of Water
- H2O(l) H2O(l) ? H3O(aq) OH-(aq)
- H3O OH- 1.00 x 10-7 M
- What is the Keq for water?
- Keq H3OOH- (1.00 x 10-7)(1.00 x 10-7)
- Keq 1.00 x 10-14 Kw
36Summary
- Kw H3OOH-
- Kw 1.00 x 10-14
37Determining H3O and OH- using Kw
- Step 1 Write the Kw expression.
- Step 2 Determine concentrations.
- Step 3 Solve!
38Example
- What is OH- in a 3.00 x 10-5 M solution of HCl?
- Kw H3OOH-
- 1 x 10-14 (3.00 x 10-5) OH-
- OH- 3.33 x 10-10 M
39Practice
- Calculate the hydronium ion concentration in an
aqueous solution of KOH that has a hydroxide ion
concentration of 7.24 x 10-4 M.
40Practice
- Calculate the hydronium ion concentration in an
aqueous solution of KOH that has a hydroxide ion
concentration of 7.24 x 10-4 M. - What is the OH- in a 0.450 M solution of HNO3?
41Practice
- 3. What is H3O in a solution of NaOH whose
concentration is 3.75 x 10-2 M?
42Practice
- 3. What is H3O in a solution of NaOH whose
concentration is 3.75 x 10-2 M? - 4. Calculate the hydroxide ion concentration of a
0.200 M solution of HClO4.
4315.2 Acidity, Basicity, and pH continued
- Objective
- To calculate pH.
44pH
- pH A value used to represent acidity or
alkalinity (basicity) of a solution.
45Measuring pH
- Indicators dyes that turn different colors in
solutions of different pH - Examples litmus paper, bromothymol blue, methyl
orange, phenolphthalein
46(No Transcript)
47Calculating pH
48Example
- What is the pH of a solution with a 0.05 M
hydronium ion concentration? - pH -logH3O
- pH -log(0.05)
- pH 1.30
- Note pH does not have units.
49Practice
- What is the pH of 0.00010 M solution of nitric
acid?
50Practice
- What is the pH of 0.00010 M solution of nitric
acid? - Calculate the pH if H3O 5.0 x 10-3 M.
51Practice
- What is the pH of 0.00010 M solution of nitric
acid? - Calculate the pH if H3O 5.0 x 10-3 M.
- What is the pH of a 0.2 M solution of a strong
acid?
5215.2 Acidity, Basicity, and pH
- Objective
- To calculate pOH.
53Calculating pOH
54Example
- What is the pH and pOH of 0.00010 M solution of
HNO3? - pH -logH3O
- pH -log(0.00010)
- pH 4.0
- pH pOH 14
- 4.0 pOH 14
- pOH 10
55Practice
- What is the pH and pOH of a 0.0136 M solution of
KOH?
56Practice
- What is the pH and pOH of a 0.0136 M solution of
KOH? - What is the pH and pOH of a 1.2 x 10-3 HBr
solution?
57Practice
- What is the pH and pOH of a 0.0136 M solution of
KOH? - What is the pH and pOH of a 1.2 x 10-3 HBr
solution? - What is the pH and pOH of a 2.34 x 10-5 NaOH
solution?
5815.2 Acidity, Basicity, and pH
- Objective
- To calculate H3O and OH- from pH.
59Calculating H3O and OH- from pH
pOH -logOH- OH- 10-pOH
60Example
- What are the concentrations of the hydronium and
hydroxide ions in a sample of rain that has a pH
of 5.05? - H3O 10-pH
- H3O 10-5.05
- H3O 8.91 x 10-6 M
- Kw H3OOH-
- 1 x 10-14 (8.91 x 10-6)OH-
- OH- 1.12 x 10-9 M
61Practice
- What is the hydronium ion concentration in a
fruit juice that has a pH of 3.3?
62Practice
- What is the hydronium ion concentration in a
fruit juice that has a pH of 3.3? - A commercial window-cleaning liquid has a pH of
11.7. What is the hydroxide ion concentration?
63Practice
- What is the hydronium ion concentration in a
fruit juice that has a pH of 3.3? - A commercial window-cleaning liquid has a pH of
11.7. What is the hydroxide ion concentration? - If the pH of a solution is 8.1, what is the
hydronium ion concentration?
6414.3 Neutralizations and Titrations
- Objective To determine the concentration of an
acid or base used to reach the equivalence point
in a titration.
65Neutralization Reaction(acid-base reaction)
- General Equation
- Acid Base ? Salt Water
- Example
- HCl NaOH ? NaCl H2O
66Titration
- Titration Method used to determine the
concentration of an acid or base.
67Equivalence Point
- Equivalence Point Point at which the
neutralization reaction is complete
68End Point
- End Point The instant at which the indicator
changes color
69Titration Calculations
- MAVA MBVB
- where A is acid and B is base
70Example
- A student titrates 40.0 mL of an HCl solution of
unknown concentration with a 0.5500 M NaOH
solution. The volume of base solution needed to
reach the equivalence point is 24.64 mL. What is
the concentration of HCl solution? - Acid (HCl) Base (NaOH)
- VA 40.0 mL VB 24.64 mL
- MA ? MB 0.5500 M
- MAVA MBVB
- MA (40.0 mL) (0.5500 M) (24.64 mL)
- MA 0.3388 M
71Practice
- If it takes 25 mL of 0.05 M HCl to neutralize 345
mL of NaOH solution, what is the concentration of
the NaOH solution?
72Practice
- If it takes 25 mL of 0.05 M HCl to neutralize 345
mL of NaOH solution, what is the concentration of
the NaOH solution? - If it takes 50 mL of 0.5 M KOH solution to
completely neutralize 125 mL of hydrochloric acid
solution, what is the concentration of
hyrochloric acid solution?
73Practice
- 3. How much 1.5 M Ca(OH)2 is necessary to exactly
neutralize 20.0 mL of 2.5 M sulfuric acid?
74Practice
- 3. How much 1.5 M Ca(OH)2 is necessary to exactly
neutralize 20.0 mL of 2.5 M sulfuric acid? - 4. A 25.0 mL sample was titrated to the endpoint
with 15.0 mL of 2.0 M NaOH. What is the molarity
of HCl?
75Practice
- 3. How much 1.5 M Ca(OH)2 is necessary to exactly
neutralize 20.0 mL of 2.5 M sulfuric acid? - 4. A 25.0 mL sample was titrated to the endpoint
with 15.0 mL of 2.0 M NaOH. What is the molarity
of Hcl? - 5. How much 0.75 M HCl is needed to completely
neutralize 25.0 mL of KOH?
7615.3 Neutralizations and Titrations
- Objective To determine the concentration of
polyprotic acids needed to reach the equivalence
point in a titration.
77Titrations with Polyprotic Acids
- MAVA MBVB
- With a twist
- MAVA (H) MBVB(OH-)
78Example
- What volume of a 1.366 M solution of NaOH would
be required to titrate 47.22 mL of a 2.075 M
solution of sulfuric acid? - Acid (H2SO4) Base (NaOH)
- MA 2.075 M MB 1.366 M
- VA 47.22 mL VB ?
- H 2 OH- 1
- MAVA (H) MBVB(OH-)
- (2.075 M) (47.22 mL) (2) (1.366 M) (VB)(1)
- VB 143.5 mL
79Practice
- How much 1.5 M NaOH is necessary to exactly
neutralize 20.0 mL of 2.5 M phosphoric acid?
80Practice
- How much 1.5 M NaOH is necessary to exactly
neutralize 20.0 mL of 2.5 M phosphoric acid? - How much 0.5 M nitric acid is necessary to
titrate 25.0 mL of 0.05 calcium hydroxide
solution to the endpoint?