Empirical and Molecular Formulas / Flipped Classroom

You are going to be taking part in a teaching experiment. The experiment is known as the "Flipped Classroom". The idea of the flip will be that you will learn about the concepts outside of class and then do your "homework" in class. You will be "lectured" on the new concepts via a series of three VODCasts (Video On Demand) from the comfort of your own home or the computer lab in the HHS library. I have made minnie movies to introduce the new concepts and to guide you through the first seven problems of the packet that you were given in class on Percent Composition, Empirical and Molecular Formulas. The VODCast files can be found on the Events Calendar of the class website under the date, Wednesday, November 2nd, 2011. It is your responsibility to view the videos, write notes on the material, and complete the example problems prior to class on Thursday, November 3rd, 2011. On that Thursday, you will come to class and work on the remaining problems of the packet in small groups. Below is a list of concepts that you need to be familiar with after viewing the VODCasts and doing the example problems in the work packet that was given to you.

• Be able to define percent composition, empirical formula, and molecular formula.
• Know the process of how to find the percent composition of individual elements in a compound.
• Know that empirical formulas are the ratios of elements in a compound based upon the counted unit of the mole.
• Know how to treat the amounts of elements in a compound when percentages are given.
• Know how to deal with a situation where the ratio of an empirical formula does not work out to be whole numbers, but rather one or more of the elements in the compound has a subscript that is a decimal / fraction number.
• Know how to determine a molecular formula by comparing the molar mass of a molecular formula to the molar mass of an empirical formula.
• Know how experimentation is needed to determine the "real" molar mass of a molecular formula. Know how relative molar masses are determined using a mass spectrometer.

Before you come to class on Thursday, November 3rd, 2011, you must have all seven example problems completed in the work packet and notes taken from the VODCasts. You will be graded on this preparation work.