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Hunter Library
Research Guides
Western Carolina University


Research help including how to find scholarly articles, property information, spectra, patents, citing sources, and more!

Chemical Abstracts Service (CAS) Registry Numbers

The fastest and most reliable way to find information about a compound in a resource is to use the Chemical Abstracts Service Registry Number (CASRN). This is like a social security number for compounds and is often used as an indexing tool in many chemistry resources. Look for it as a series of three numbers, often inside of square brackets:  [XXXX-XX-X].

To lookup a compound's CASRN, search one of the below resources using the compound's name.

Property Information: Online

Property Information: In Print

HazMat Information