Mass Spectrometry gives the molecular weight of different components of a molecule. It can be used in conjunction with Gas Chromatography (GC-MS) to identify the molecular masses of components of a mixture. Gaseous molecules are ionized with a beam of electrons. The radical cation then breaks apart into charged and uncharged segments of different molecular weights, with the most stable being the most common (common fragmentation patterns can be identified, like the McLafferty Rearrangement for carbonyls). The particles are then passed through a magnetic field which separates them based on their mass-to-charge ratio (m/z). The biggest peak is called the base peak and set to a value of 100. Isotopes like Carbon-13 as well as Cl-35 and Cl-37 are important because the molecular masses are a weighted average of the isotopes. Examples in this lecture include chloroethane, bromobutane, hexane, ethers, alkenes, amines, and aromatic groups.
Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.