The analysis of the vapors from six commercial glues provided an interesting and challenging lab assignment for students in an instrumental analysis laboratory course. Students used both electron impact (EI) and chemical ionization (CI) modes of operation in GC–MS to identify the volatile components in their assigned glue. Chemical ionization using methane as the reagent gas provided a complementary analysis to the more common EI mode of operation. In the softer CI mode, there is a higher probability of observing the molecular ion. Students were required to explain the observation of specific mass fragments observed from both EI and CI operations in terms of their reactions in the ion source of the mass spectrometer. This interpretation of mass spectra provided the students an educational exercise for understanding the ionization processes that occur in mass spectroscopy.
Supplement
Instructions for the students, notes for the instructor, and data from the experiment are available.
Our Secondary School editors work hard to distill all the JCE materials to produce a fraction of particular interest to high school teachers. We call it CLIC.
In recent years we have worked hard to better match our advertisers with our readers. When shopping for chemistry education materials, visit our advertisers' WWW sites first.
Take JCE along on your outreach missions. Copies of the Journal, guest access to JCE Online, our publications catalog, and more are available for your participants.