General Chemistry Spring 2009

In today's class we began discussing the types of solid and then we looked at simple cubic. We discussed the relationship between edge length and atomic radius and we did a sample problem using simple cubic cells.

In today's class we discussed polarizibility and its importaqnce in dispersion forces. We then turned to vapor pressure, its definition, a particulate animation depicting vapor pressure, the comparison of vapor pressure and pressure due to vapor, and the temperature dependence of vapor pressure in the Clausius-Clapeyron equation.

In today's class we discussed intramolecular (ionic bonds and covalent bonds) and intermolecular attractive forces (hydrogen-bonding, dipole-dipole and London dispersion forces).

In today's class we talked further about entropy and free energy and how to calculate the values.

In today's class we talked about enthalpy and looked at the DCI on Enthalpy and the First Law. We reviewed how to calculate the enthalpy change of a chemical reaction and discussed endothermic and exothermic reactions. We defined spontaneity and considered whether enthalpy was sufficient to predict whether a chemical reaction is spontaneous. We found that we needed to also consider entropy, so we introduced entropy and discussed the 2nd and third laws of thermodynamics. We discussed how to calculate the change in entropy for a chemical reaction.

The majority of this class dwelled on administrative details of CHEM 1515 SPRING 2009 and the course web site. During the last 15 minutes of class we started discussing Chapter 20: Thermodynamics 2nd and 3rd Law.

In this clip I discuss several multiple choice questions over gas laws and bonding.

In this clip I do three problems. The first is a limiting reagent problem using the ideal gas law, the second is a sample bond energy calculation and the last problem is about identifying what type of hybrid orbitals and atomic orbitals are involved in bonding between two atoms in a compound.

In today's class we tried to discussed the solution process but class was interrupted by a tornado warning.

In this lecture we continued our discussion of hybrid orbitals on central atoms that are used to form covalent bonds. We briefly reviewed sp^3 hybrid orbitals, then we talked about sp^2 and sp hybrid orbitals. Next we looked at the bonding in ethene (ethylene) to show how we view a double bond. We discussed sigma and pi bonds. We also looked at ethyne (acetylene) to see the nature of the bonding in that molecule. We discussed nitrite as an example of a polyatomic anion that exhibits delocalize electrons. Finally we started talking about gases. We did a demonstration of atmospheric pressure and looked at the PLE experiment that everyone did for class.