Spring 2019

Syllabus

Continuously updated. You should check this BEFORE EACH class so you prepare adequately!
Approximate associated sections of the text are in parenthesis. Read these BEFORE class along with any other information provided for each class day. (There might be a quiz.)

28 Jan    What is Energy?
             Make sure you know the energy definitions covered in 1.5. What other types of Energy have you heard about?
             Review your CHEM151 materials for definitions and calculations of Energy. (Always bring your calculator to class!)
30 Jan    The First Law, Work (9.1-9.2)
             Besides knowing definitions, pay attention to positive and negative signs indicating the direction of energy flow.
             In calculations, be aware of units and review last semester's chapter on gases if necessary.
01 Feb    Heat, Enthalpy and Calorimetry (9.3-9.5)
             Note that you may treat Enthalpy Change (delta-H) and Heat (q) synonymously.
             Be careful of the multiple ways that heat capacity can be expressed.
             As you can tell from everything we've done so far, definitions are important and pay attention to +/- signs!

04 Feb    Standard Enthalpies of Formation and Hess' Law (9.6-9.7)
             The reason any of these calculations work is because enthalpy is a state function!
             Be sure you can draw energy diagrams representing endothermic and exothermic reactions.
             You can skip the Bond Energies section for now, we'll cover it next week.
06 Feb    Some Enthalpy Changes in Ionic Compounds (9.8)
             Before class, look over CHEM151 notes to make sure you know:
             • what I.E., E.A. and lattice energies are, their signs (positive/negative) and factors affecting their relative magnitudes.
             • what factors affect the relative solubility of ionic compounds
08 Feb    Burning Fuels, Standard Enthalpies of Combustion (9.7,9.9)
             If you didn't cover Line Structures in CHEM151, read this primer before class on Line Structures
             Appendix 4 is your friend. You'll be using it a lot.
             While we will use combustion as an example, similar strategies can be used to calculate enthalpy changes for any chemical reaction.

11 Feb    Bond Energies and Reaction Enthalpy (4.5,9.7)
             Be careful of the signs. It depends on how you define bond energy.
             For CO2, the exact bond energy is 800 kJ/mol, very different from the average C=O in Table 4.6 and Appendix 4.
             Note (in Table 4.6) that bond strength is affected by whether they are multiple, how long they are, and their relative polarity (recall the definition of electronegativity).
13 Feb    Entropy and the Second Law (12.1-12.2)
             Watch these three videos before class and think about the questions posed.
             Important Concepts: Spontaneity, Entropy, Second Law
             In particular, it is important to recognize situations in which entropy increases or decreases.
15 Feb    Entropy at the Molecular Level (12.2-12.3,12.5)
             Watch this video before class: www.youtube.com/watch?v=RjOqaD5tWB0. What are some possible causes for the phenomena observed?
             Entropy turns out to be a matter of probabilities and perception (i.e., how you "group" things.)
             You should be able to calculate the change in entropy of the system given standard molar entropies, and explain if your results make sense.

18 Feb    Entropy Changes in System and Surroundings (12.4)
             A second way to find deltaS of the system is to run a reaction under reversible conditions.
             In CHEM152, a reaction under reversible conditions (both forward reactions are running at the same rate) is said to be at equilibrium.
20 Feb    Free Energy and Spontaneity (12.6)
             One of the most important equations in CHEM152 is deltaG = deltaH - T deltaS
             While standard free energies of formation are in Appendix 4, it's more important to calculate deltaH and deltaS separately, because it's important to interpret how each affects deltaG.
22 Feb    Thermodynamics and Phase Changes (12.7)
             Besides knowing the signs of deltaH and deltaS for phase changes, you should be able to calculate T under reversible conditions.
             Revisit Figures 9.13 and 12.8. You should be able to make arguments for the relative magnitudes of deltaH and deltaS for phase changes.

Take-Home Exam #1 this weekend.

25 Feb    Burning Fuels Again: Reconsidering Efficiency
             We can now calculate free energies of combustion! You should know how to do this based on previous classes.
27 Feb    Thermodynamics of Life: Coupling Reactions (12.8)
             How do you get uphill reactions to "go"? By coupling them with an appropriate downhill reaction.
01 Mar   Osmosis (11.1-11.2)
             You should know the definition of osmosis and be able to predict the flow of a solution due to osmotic pressure.
             You should know how to determine ideal van't Hoff factors in aqueous solutions and use the osmotic pressure equation.
             In the second half of class, we will briefly consider the (chemical) origin of Life!

SPRING BREAK

11 Mar   Vapor Pressure and Raoult's Law (11.3-11.4)
             You should know the similarities and differences between evaporation and boiling.
             Be able to explain why evaporation occurs and describe how it changes with temperature.
             You can skip the Clausius-Clapeyron equation in 11.3 and the initial discussion of fractional distillation in 11.4.
             You should be able to explain the effect of solute on vapor pressure including making a thermodynamic argument.
             You should be able to use Raoult's Law to describe and calculate the vapor pressure of mixtures, including why there might be positive and negative deviations from Raoult's Law.
13 Mar   Colligative Properties and Henry's Law (11.5-11.6)
             Make sure you know how to calculate the molality of a solution (and the definition of molality).
             You should be able to do calculations using Henry's Law.
             You should be able to explain how solutes change the normal melting point and boiling point of water, and calculate the change in boiling point elevation and freezing point depression.
15 Mar   Rates of Reactions (13.1-13.3)
             Important things to know how to do:
             • Understand, write and use the rate of reaction expression (in 13.2).
             • Write a rate law and understand how orders impact reaction rate.
             • Determine the rate law using Method of Initial Rates
             We'll cover Integrated Rate Laws in the next class.

18 Mar   Integrated Rate Law (13.3)
             Make sure you can correlate the straight-line graph and its corresponding equation to the appropriate order of reaction.
             Know the definition of half-life and how to calculate it for different reaction orders.
             In class we will discuss strategies to find the rate law given a data table.
20 Mar   How Temperature affects Rates (13.4)
             The Arrhenius equation is key here. Make sure you can use it qualitatively and quantitatively in the natural-log (ln) form.
             You should know the definition of activation energy and how to represent it on an energy diagram.
22 Mar   Linking Mechanisms to Rate Law (13.5)
             Know the definition of an elementary reaction. In a multi-step mechanism, each step is always elementary (following the law of mass action).
             Given a reaction mechanism and the slow step, you should be able to write the rate law.
             Given a rate law, any proposed mechanism can either be consistent or inconsistent with it.

25 Mar   Catalysis (13.6)
             The definition of a catalyst is important and you should be able to represent that definition in an energy diagram.
             Also you should be able to identify catalysts in a multi-step reaction and distinguish it from an intermediate.
27 Mar   Membranes: Creating Primordial Cells
             The reading will be e-mailed to you on 25 Mar along with discussion questions for today's class.
29 Mar   Chemical Equilibrium (14.1-14.4)
             Equilibrium is the eventual fate of all chemical reactions in a closed system.
             Given a balanced equation, you should be able to write an expression for the equilibrium constant, K.

Take-Home Exam #2 this weekend.

01 Apr    No class today
03 Apr    Le Chatelier's Principle (14.5-14.7)
             You should know the definition of Q (reaction quotient) and how it differs from K, and predict which way a reaction will proceed.
             Be sure to know the definition of Le Chatelier's Principle and be able to use it in different situations.
             We will cover: concentration changes, external P changes, T changes, and adding a catalyst.
05 Apr    Calculations with Equilibrium Constants (14.8)
             There will be lots of numerical problems to solve.

08 Apr    Linking Equilibria, Kinetics and Free Energy (14.9-14.10)
             Read this post from The Curious Wavefunction: The two equations you should know
             The three important equations from this section are 14.20, 14.19 and 14.25; the last one can be derived from the straight-line plot.
10 Apr    Acids and Bases (15.1-15.4)
             The Arrhenius and Bronsted-Lowry definitions of acids and bases (and their conjugates) is important.
             For any acid, you should be able to write its dissociation reaction and an expression for K_a. (Similarly for bases and K_b).
             Be sure you know how K_a relates to acid strength (and K_b to base strength).
             Know the definition and value of K_w at standard conditions.
             From last semester, you should know the definition of pH.
             In class, we will discuss qualitative factors that affect acid strength.
12 Apr    Weak Acid and Base Equilibria, Part 1 (15.5-15.7)
             Given K_a, you should be able to calculate pH and vice versa.
             Know the definition of pK_a and be able to use or calculate it.
             Be able to calculate the percent ionization of a weak acid. Polyprotic acid problems are similar to multi-step monoprotic acid problems.

15 Apr    Weak Acid and Base Equilibria, Part 2 (15.5-15.7)
             Given K_b you should be able to calculate pH and vice versa.
             Polyprotic acid problems are similar to multi-step monoprotic acid problems.
17 Apr    Acidic and Basic Salts (15.8)
             You should know how to use K_a.K_b = K_w for a conjugate acid-base pair.
             We will make arguments to predict if a salt is likely to be acidic, basic or neutral by identifying conjugates.

EASTER BREAK

24 Apr    Buffer Solutions, Part 1 (16.1-16.3)
             Be sure to know the definition of a buffer solution and how to identify one based on concentrations of chemical species.
             The Henderson-Hasselbach (Buffer) Equation is crucial will be used multiple times throughout this chapter.
26 Apr    Buffer Solutions, Part 2 (16.1-16.3)
             You should be able to calculate the pH changes as acids or bases are added to a buffer solution and evaluate buffering capacity.
             We will discuss in detail how one goes about preparing a buffer solution practically.

29 Apr    Acid-Base Titration Curves (16.4)
             After today's class, you should know how to sketch any titration curve, identify the four main regions, and the major species in each region.
             This will help you solve numerical problems related to titration.
             You should be able to calculate pH at any point on the titration curve, but especially at the midpoint and equivalence point.
01 May   Solubility Equilibria (16.8)
             Be able to write an equation for the dissolving of ionic compounds, along with an expression for K_sp.
             Given K_sp and calculating Q, predict if a precipitate will be observed.
             Given saturation concentrations and/or masses, be able to calculate K_sp and vice versa.
03 May   Lewis Acids & Bases (16.5)
             You should know the definition of Lewis Acids and Bases, be able to identify them, and rank them by strength.

Take-Home Exam #3 this weekend.

06 May   Complex Ion Formation (16.6-16.7)
             Define and use K_f, the equilibrium constant for complex ion formation.
             Because K_f is usually a large number, the calculations take a little more work as we'll see in class.
08 May   Electrochemistry and Galvanic Cells (17.1-17.2)
             Be sure you can identify all parts of the galvanic cell and represent it in shorthand notation.
             Be able to write half-reactions and net ionic equation for an electrochemical cell.
10 May   Standard Reduction Potentials (17.3,17.5)
             Don't confuse the cell potential with standard reduction potentials! You can use the latter to calculate the former.
             You should be able to predict which way a reaction will proceed in a galvanic cell using the Activity Series.
             You should also be able to calculate E and E_cell for galvanic cells.

13 May   Free Energy and Electrochemistry (17.4,17.6)
             The equation connecting deltaG to cell potential is important!
             Be sure you can use the Nernst equation.
15 May   Q-and-A before Final, Applications of Electrochemistry(17.7-17.9)
             You should qualitatively be able to describe electrochemistry applications we discuss in class.
             Note particularly the difference between a voltaic cell and an electrolytic cell (see Figure 17.9).
             Come with questions about the Final! I might have answers.

Final Exam is Mon, May 20, 8-10am in class.
Equations for Final Exam