I. Colligative Properties (Chapter 8A)

Define molarity, molality, and mole fraction. Be able to express solution composition in terms of each of these units. Be able to convert between these units. What information is needed to convert from molality to molarity? Why is molality a better unit than molarity for very precise work? What is "fundamental" about the mole fraction unit?

What is meant by the term colligative properties? What are the three colligative properties discussed in class and how do they depend on the number of dissolved particles? Using a molecular level picture, explain why vapor pressure is lowered in a solution as compared to the pure solvent. What is an ideal solution and what is Raoult’s law? Use Raoult’s law to calculate the vapor pressure lowering of a solution. How is the phase diagram of a pure solvent different than that of a solution? Use the phase diagram to show why boiling points are elevated and freezing points are depressed in a solution. Why is the vapor over a solution of a volatile nonelectrolyte richer in the more volatile component? Why is CaCl₂ better at melting ice on sidewalks than NaCl? Be able to utilize the appropriate formulas to determine boiling points and melting points of ideal solutions.

What are soaps and detergents made from? What structural features of a molecule make it behave like a soap? How does soap work? What is the difference between a soap and a detergent?

II. The Solid State (Chapter 9)

What is the difference between crystalline, amorphous, and polycrystalline solids? What are the five types of solids discussed in class? Give examples of substances that fit each type. What are the typical properties of each type of solid? What interparticle forces hold each type of solid together? Given the formula of a substance be able to determine the type of solid it would form (using bond-type triangles if necessary). What are some useful measures of interparticle forces in molecular and atomic solids? Be able to predict trends in melting point and enthalpy of fusion for related sets of molecular or atomic solids (example: which substance would have the largest melting point? HF, HBr, HCl, or HI). What force holds ionic solids together? How does this force depend on the ionic charges and the distance between neighboring ions? How is lattice energy defined? How is lattice energy related to melting point? Be able to construct a reaction diagram (see page 356) and be able to calculate lattice energy from enthalpies of atom combination, ionization energies and electron affinities. What is electron affinity? Be able to predict which ionic compound in a given series will have the largest lattice energy.

What are some distinctive characteristics of metallic bonding? What is enthalpy of atomization? How is it related to metallic bond strength and hardness? How does metallic bonding explain the characteristic properties of metals?

Describe the expected properties of semimetals. Of what is glass composed? What is the difference between sand and glass on a molecular/microscopic level? What are ceramics and how are they made? What are the potential applications of modern ceramics? What is a superconductor and what are the applications for these materials? What is the Meissner effect?

What is a crystal lattice? Describe the concept of unit cell. Why is the unit cell a useful concept? What is coordination number? What are the names of the 7 basic crystal systems? What are the three types of unit cells in the cubic crystal system? Be able to draw sketches of each. What is the coordination number of the atoms in each of these unit cells? How many atoms are contained in each of these unit cells?

What is meant by packing efficiency? What is the packing efficiency of each type of cubic unit cell? How does packing give rise to the cubic and hexagonal unit cells? What is meant by the term closest packing? What types of unit cells are closest packed structures? What is the layer stacking patter for each type of closest packed structure? What is the connection between unit cell packing and density? Knowing unit cell type and density, be able to calculate: unit cell volume, unit cell edge length, and atomic radius (or calculate density knowing radius). Given a unit cell be able to count the number of atoms (of each type) that it contains.

How are crystal structures determined in the lab? Be able to sketch the basic x-ray diffractometer apparatus.

II. Chemical Kinetics & Equilibrium (Chapter 10: section 10.1 – 10.9, worksheet, CA39, CA40)

How is the rate of a chemical reaction defined? What are the units on rate? Given the equation for a chemical reaction be able to write ALL of the equivalent expressions for rate. What are the premises of the collision theory of rates? How can rates of reaction be changed? Explain by making use of collision theory. Show how the energy changes as a reaction proceeds from reactants to products. What is a transition state? What is activation energy? Why do we say that all reactions are reversible in principle? What is a rate law? What is a rate constant? What are reaction orders? How can a rate law be used to calculate rate of reaction?

What would a sketch of reactant or product concentration as a function of time look like? On that sketch be able to identify the equilibrium region, the kinetic region, and the equilibrium concentrations. How could you determine rate of production of a product or rate of consumption of a reactant from this graph? What is meant by dynamic chemical equilibrium? For chemical reactions, what is the connection between equilibrium and reaction rates?

What does the "law of mass action" state? Is the equilibrium constant really constant? How do the forward and reverse reaction rate constants effect the equilibrium constant? Given any balanced chemical reaction, be able to write the corresponding equilibrium constant expression. Be able to use all six properties of equilibrium constants that we discovered in class. Be able to rework problems presented in class or assigned on the homework. Knowing the value of K_c, be able to predict whether a reaction favors the reactants or products. What is the reaction quotient? What does the reaction quotient tell you? Knowing or calculating the value of the reaction quotient be able to predict whether the reaction will proceed towards the reactants or products to reach equilibrium. Distinguish between homogeneous and heterogeneous equilibria. Why do we leave the concentrations of pure liquids and pure solids out of equilibrium constant expressions?

To calculate the equilibrium constant you first need to know the equilibrium concentrations of all reactants and products (except pure solids and liquids). Be able to use experimental data and stoichiometry to calculate the value of equilibrium constants. Use the relationship between K_c and K_p (you do not need to memorize this) to compute one from the known value of the other.

Use a given value of the equilibrium constant for a reaction to compute the equilibrium concentrations (or partial pressures) of all species present in a reaction mixture. Practice working sample problems in sections 10.7 & 10.8 and related homework problems.