Books are shelved in general subject categories using the Library of Congress classification system. You may want to supplement your use of the catalog with browsing shelf areas for your topic. Below is a brief listing of some of the subject locations in the field of chemistry. The general collection books (books you can check out) for chemistry are all located on the main floor.
Chemistry
Encyclopedia of the Elements by 
The World of Chemistry by This work is licensed under CC BY-NC-SA 4.0
