Module 5 Acids, Bases, and Solubility Equilibrium
CHEM-1312 M5L1 Explore: Properties of Acids and Bases
Overview
What You Will Learn
- Brønsted Acids and Bases
- We start by reviewing and extending Brønsted’s definitions of acids and bases (in Chapter 4) in terms of acid-base conjugate pairs. (15.1)
- The Acid-Base Properties of Water
- Next, we examine the acid-base properties of water and define the ion-product constant for the autoionization of water to give H1 and OH2 ions. (15.2)
- pH—A Measure of Acidity
- We define pH as a measure of acidity and also introduce the pOH scale. We see that the acidity of a solution depends on the relative concentrations of H1 and OH2 ions. (15.3)
- Strength of Acids and Bases
- Acids and bases can be classified as strong or weak, depending on the extent of their ionization in solution. (15.4)
- Weak Acids and Acid Ionization Constants
- We learn to calculate the pH of a weak acid solution from its concentration and ionization constant and to perform similar calculations for weak bases. (15.5 and 15.6)
- Weak Bases and Base Ionization Constants
- We derive an important relationship between the acid and base ionization constants of a conjugate pair. (15.7)
- The Relationship Between the Ionization Constants of Acids and Their Conjugate Bases
- We then study diprotic and polyprotic acids. (15.8)
- Diprotic and Polyprotic Acids
- We continue by exploring the relationship between acid strength and molecular structure. (15.9)
- Molecular Structure and the Strength of Acids
- We continue by exploring the relationship between acid strength and molecular structure. (15.9)
- Acid-Base Properties of Salts
- The reactions between salts and water can be studied in terms of acid and base ionizations of the individual cations and anions making up the salt. (15.10)
- Acid-Base Properties of Oxides and Hydroxides
- Oxides and hydroxides can be classified as acidic, basic, and amphoteric. (15.11)
- Lewis Acids and Bases
- The chapter concludes with a discussion of Lewis acids and Lewis bases. A Lewis acid is an electron acceptor and a Lewis base is an electron donor. (15.12)
- Oxides and hydroxides can be classified as acidic, basic, and amphoteric. (15.11)
- The chapter concludes with a discussion of Lewis acids and Lewis bases. A Lewis acid is an electron acceptor and a Lewis base is an electron donor. (15.12)
What to Read
Overby/Chang: Chemistry, 14th Ed. - Chapter 15
Media
Acids and Bases Intro
Time: 8:38 min.
Topics: Brønsted-Lowry acid-base theory, proton transfer, conjugate acid-base pairs, amphoteric substances, relative acid-base strength relationship
Acids and Bases: Properties of Water
Time: 6:11 min.
Topics: Amphoteric nature of water, auto-ionization of water, ion product constant (Kw), relationship between [H3O+] and [OH-] in aqueous solutions:
pH - Measuring Acidity
Time: 6:08 min.
TTopics: pH definition and scale, relationship between [H3O+] and pH, acidic vs basic vs neutral solutions, antilog calculations for concentration
pOH
Time: 2:50
Topics: pOH definition, relationship between pH and pOH, pKw calculations, hydroxide ion concentration calculations
pK (pKa and pKb)
Time: 4:13 min.
Topics: pK calculations, relationship between Ka and pKa, Kb and pKb, logarithmic relationships in acid-base chemistry
Strength of Acids and Bases
Time: 4:55 min.
Topics: Ionization constants (Ka/Kb), strong vs weak acids, acid/base dissociation, relationship between acid strength and conjugate base strength
Cations as Weak Acids
Time: 4:13 min.
Topics: Cations acting as weak acids, hydrolysis reactions, effect on solution pH, examples of acidic cations
Percent Ionization
Time: 2:59 min.
Topics: Percent ionization calculations for weak acids, relationship between concentration and percent ionization, practical applications
Weak bases and Base Ionization Constant
Time: 1:56 min.
Topics: Weak base equilibria, Kb calculations, relationship between Ka and Kb for conjugate pairs, base ionization calculations
Diprotic and Triprotic Acids
Time: 3:23 min.
Topics: Polyprotic acid systems, stepwise ionization, multiple Ka values, pH calculations for polyprotic systems
Strength of Binary Acids
Time: 3:21 min.
Topics: Binary acid trends, relationship between molecular structure and acid strength, periodic trends affecting acidity
Supplemental Resources
An extremely flexible and informative periodic table: Periodic table
Periodic Table: Offline Version
(Practice) Everyday Chemistry in your life:
- List some common liquids that you think are acidic or basic. For example, do you think orange juice is acid or base? Why do you think each liquid is an acid or base?
- orange juice is ( Acid or base) and (Why do you think so?)
- #2 is ( Acid or base) and (Why do you think so?)
- Do you think the amount of the liquid changes how acidic or basic it is? Explain your thinking.
- What do you think adding water (dilution) changes how acidic or basic the liquid is? Explain your thinking.
- Use pH Scale Basics to test your ideas about some common things that are acids or bases.
Test your understanding and self-check: For each question, predict your answer and support your answer with an explanation.
Then use pH Scale Basics to verify and add screen captures to your explanation.
- Prediction and explanation with support
credit: PhET, phet.colorado.edu, ph-scale-basics
2. Prediction and explanation with support
credit: PhET, phet.colorado.edu, ph-scale-basics
3. Prediction and explanation with support
credit: PhET, phet.colorado.edu, ph-scale-basics
4. Prediction and explanation with support
credit: PhET, phet.colorado.edu, ph-scale-basics
5. Prediction and explanation with support
credit: PhET, phet.colorado.edu, ph-scale-basics