General Chemistry II Student Competencies

Chemistry: The Central Science, Brown, Lemay, and Bursten, 2000.

Chapter 14	Chapter 15	Chapter 16	Chapter 17

Chapter 14 Student competencies

Upon completion of this chapter, students should be able to:

Use kinetic-molecular theory to explain how reactions occur. Be able to explain the underlying reason for why concentration and temperature changes affect reaction rates.
Understand the main factors that control the rate of a reaction.
Understand exactly what “reaction rate” means and be able to calculate the rate of a reaction when given data showing concentrations at various times.
Be able to use reaction stoichiometry to write the rate of a reaction in terms of how each product or reactant concentration changes with time
Given a set of data showing reaction rates for various combinations of concentrations, calculate the rate law and the rate constant.
Be able the write the rate law expression. Understand the units associated with rate, what reaction order is, and how the units of the rate constant k vary with reaction order.
Understand and be able to use the Arrhenius expression:

Be able to show how the Arrhenius equation accounts for collision frequency and orientation factors
Know how to determine the fraction of molecules with sufficient energy to react at a given temperature for a given activation energy.
Demonstrate an understanding of how to graphically determine the activation energy for a given reaction.
Given rate constants at multiple temperatures, know how to calculate the activation energy for the reaction. From the activation energy and rate constant at one temperature, be able to predict the rate constant at any other temperature.

Understand first order reactions:

Be able to write the rate law for such a reaction
Know and be able to use the expression for how concentration changes with time in a first order reaction
Know and be able to use the expression that relates the half-life with the rate constant for a first order reaction.
Explain graphically what parameters to plot to show if a reaction is a first order process.

Understand second order reactions:

Be able to write the rate law for such a reaction
Know and be able to use the expression for how concentration changes with time in a second order reaction
Know and be able to use the expression that relates the half-life with the rate constant for a second order reaction.
Explain graphically what parameters to plot to show if a reaction is a second order process.

Understand how reaction rate varies with temperature and the two underlying reasons for this. Use a kinetic molecular distribution diagram and an energy reaction coordinate diagram to explain this.
Understand and be able to depict the change in enthalpy, the activated complex, and the activation energies for a forward and reverse reaction on an energy reaction coordinate diagram.
Explain what is meant by a reaction mechanism; be able to write the rate laws for elementary steps and to clearly outline the significance of the rate-determining step. Understand the terminology associated with reaction mechanisms.
Given that a specific step in the reaction mechanism is identified as the slowest step, predict the rate law associated with this mechanism.
Use an energy diagram to explain how a catalyst affects reaction rates.
Explain how heterogeneous and homogeneous catalysts work.
Understand the role of enzymes in living systems to include:

The lock-and-key model of enzyme action and an understanding of the active site.
The specific types of interactions that occur between substrates and enzymes
The importance of enzyme inhibition and turnover number and how these are related to toxic effects and activation energies respectively.

Identify the three major pollutants from automobiles and outline the reactions that each undergo in catalytic converters.

Chapter15 Student competencies

Upon completion of this chapter, students should be able to:

Relate forward and reverse reaction rates to equilibria and to equilibrium constants.
Know what is meant by the Law of Mass Action. For both homogeneous and heterogeneous reactions, be able to write the expression for the equilibrium constants K_c and K_p. Relate the value of the equilibrium constant to the position of equilibrium.
Given concentrations or pressures, determine the value of the equilibrium constant. Be able to relate K_c and K_p.
Understand the factors that change the equilibrium constant.
Know what is meant by the reaction quotient Q. Given a set of concentrations and the equilibrium constant, determine whether a particular reaction is at equilibrium. If it is not, predict which way it would spontaneously shift to reach equilibrium.
Given a set of initial concentrations and the equilibrium constant, calculate the equilibrium concentrations.
Understand Le Chatelier's principle and be able to explicitly state it. Understand how equilibria respond to pressure, temperature, and concentration changes. Be able to explain why in terms of the relative effects on the forward and reverse reaction rates.
Understand how a catalyst affects equilibria.

Chapter 16 Student competencies

Upon completion of this chapter, students should be able to:

Be able to define and identify Arrhenius, Bronsted-Lowry, and Lewis acids and bases.
Given the pH, pOH, [OH^-], or [H₃O⁺}; be able to quickly calculate the other three to the correct number of significant figures.
Understand what is meant by conjugate acid-base pairs and how the strength of one is related to the weakness of the other.
Understand the K_w equilibrium and explain what the pH scale represents.
Be able to identify the strong acids and bases and to calculate the pH, or pOH for a given concentration.
Relate the K_aof an acid to the K_b of its conjugate base.
From the K_a and an initial concentration, be able to determine the pH of a weak acid solution. From the K_b and an initial concentration, be able to determine the pOH of a weak base solution.
Be able to identify weak acids and weak bases and to write the reaction of each with water.
Show the reactions that occur for polyprotic acids.
Be able to identify a species that can act as an acid or as a base; be able to determine whether a solution of this species would be acidic basic, or neutral.
Understand the acid-base properties of a salt solution. Given a salt, be able to write the hydrolysis reactions of each of its ions (cation and anion) with water. Use these to predict whether the reaction would be acidic, basic, or neutral.
Understand the three main factors (bond polarity, bond strength, and stability of conjugate base anion) that affect acid strength; use these to rank order a series of structures in terms of their acidity or basicity.
Understand the relative acidity of oxyacids with differing number of oxygen atoms.
Be familiar with the structure of carboxylic acids and understand why they are acidic.
Understand and be able to diagram how metal ions not in Groups I or II react with water. Relate acidity of metal ions to charge and size. Discuss acidity of these metal ions in terms of Lewis acids and bases.
Be able to determine the percent ionization for a weak acid or base solution.

Chapter 17 Student competencies

Know what is meant by a buffer and understand the pH range over which buffers are typically considered to be effective.
Know the Henderson-Hasselbalch equation; demonstrate an understanding of how to use it to prepare buffers and to calculate the pH of a given solution of an acid/conjugate base pair. Relate the pH of a buffer system to the relative concentrations of the acid/conjugate base pair.
For a given buffer system, write the reactions that would occur with the addition of a strong base and with the addition of a strong acid.
Understand how to carry out an acid-base titration calculation.
For the titration of a weak base with a strong acid; outline what type of solution remains at the equivalence point. Be able to do the same for the titration of a weak acid with a strong base.
For a given ionic salt that has low solubility in water, demonstrate an understanding of solubility equilibria and of K_sp.
For a given K_sp, calculate the solubility for the salt. For a given solubility (given in M or in mg/dL), know how to determine K_sp.
Determine the solubility of a substance in a solution that already contains one of the ions present in the salt.
For salts with basic anions, predict the effect of pH on solubility; demonstrate an understanding of the underlying reasons for this using all appropriate equilibria and Le Chatelier's principle.
Understand and diagram what a complex ion is; identify the Lewis acid and base. Know the equilibria for complex ion formation. Discuss how complexes affect the solubility of metal ions by showing appropriate equilibria. Understand the role of complex ions in the human body..
For partially soluble salts with non Group I or II metal ions, predict the effect of ligand concentrations (e.g. NH₃) on solubility. Show the underlying reasons for this using all appropriate equilibria and Le Chatelier's principle.