Today we carefully went over the last two quizzes. The gas law quiz will be repeated tomorrow after class for anyone who hopes to earn a better score. The key point is that it is important to classify a problem type to know how to proceed. The main three types of gas law problems are ones based on the combined gas law (changes in conditions), ones based on the ideal gas law (usually combined with stoichiometry), and ones about density (learn the density equation).
The thermodynamics quiz was a bit better but many errors were made from a kind of carelessness. It is very important to order your thoughts and to order your work – take up the space you need.
After working on the quizzes for awhile we took a sparkler break. The chemistry of fireworks typically involves a strong oxidizing agent like potassium chlorate or potassium nitrate. Both of these provide oxygen that is then used to support the combustion of other materials.
After our break it was back to quantum chemsitry. You should know the three main experiments that could not be explained by classical physics, the ten scientists and their major contribution to atomic theory, and the rules for the four quantum numbers: n, l, ml, and s. Each quantum number tells us something about the electrons in orbitals: size, shape, orientation and electron spin. The contours we see for these orbitals are deceptive – the orbitals are probability equations. They predict the probablity of finding an electron in a certain place. The electrons have specific energies, quantized energies. They move from one orbital to another by the absorption and emission of photons. (We also looked at the vocabular of light interactions with matter.)
All in all it was a very busy day.