General Chemistry Spring 2009

In today's class we discuss Le Chatelier's Principle. We covered the effects of changing concentration, pressure and temperature on a reaction at equilibrium. At the end of class we began discussing the quantitative effect of changing temperature on a reaction at equilibrium..

In today's class we began a discussion of oxidation and reduction reactions. We looked at a set of reactions to look for patterns. Based on the patterns in the reactions we discuss an early definition of oxidation and reduction, gain (oxidation) of oxygen atoms and loss (reduction) of oxygen atoms. Next we discussed oxidation-reduction in terms of electron loss and gain. We introduced half-reactions, and oxidizing and reducing agents. Then we looked a balancing oxidation-reduction reactions. We discussed balancing in acidic solutions and basic solutions.

Exam II from Spring 2008 CHEM 1515

In this segment I worked out all but the multiple choice questions on the Exam #3 for the Spring 2006 semester. This will be an excellent review for the final.

In this clip I do several problems on a comprehensive final exam. The first is our standard first problem where we must predict the products of a particular chemical reaction, identify the phase of each product and balance the equation. The second problem I write the ionic and net ionic equation for one of the reactions in question 1. The 3rd question is a complicated conversion problem. The final question on this part consists of three essay questions; one on ionization energy, a second on the hydrogen atom and a third on polarity of molecules.

In this lecture we began by reviewing the effective nuclear charge. The ACA for today's class had some questions on ENC that many students had difficulty with, so we did a brief review. Next we discussed the two anomilies in the first ionization energies for the 2nd period elements. Then we defined electron affinity and looked at the experimental values for the elements in the 2nd period and discussed the trend. Next we began discussing Chapter 8 Chemical Bonding. We began witha review of ionic and covalent compounds and their properties. We looked at the Lewis structure of atoms, and the symbolic representation of the valence electrons. We discussed ionic bonding and covalent bonding and looked a several examples. We discussed lattice energy as a measure of the strength of an ionic bond. Right an the end of class we looked at an animation depicting the overlap of two hydrogen 1s orbitals to form a covalent bond.

In this lecture we began by looking at what happens when water freezes. We then continued our discussion by reviewing types of solids. We then discussed different types of crystal systems solids can have. We focused on the cubic system and discuss simple cubic, body-centered cubic and face centered cubic. We looked at each of the unit cells for these systsms and discussed the relationship between edge length and atomic radisu. Near the end of class we did a sample calculation of a problem based on a cubic system..

In this clip I go over how to access some of the resources you will need to run animations on the CHEM 1515 web site. I discuss and demonstrate how to access the Java RunTime Environment that you will need to run any of the animations created by Kirk Haines, Dr. Abraham and myself that are included in the DCI and Computer Lab Activities Workbook. I also demonstrate how to access the Molecular Workbench animations.

This segment covers questions asked by students about PS#13 and PS#14 on Thursday, December 7, 2006. THe questions asked on PS#13 were problems 4, 5, 6 and 7. On PS#14 problems 2, 3 and 5 were asked. A question on the Boltzman distribution (range of speeds of particles in a sampe of gas) was also asked.

In this segment I do go over how to answer PS3.10a and PS3.10b. These are both good, challenging problems that you will want to review to be sure you understand. Checkout Sample Exercise 3.15 on Page 99, and Execises 3.51 - 3.54 at the end of the chapter.