Substance Search

Welcome to Common Chemistry from Chemical Abstracts Service (CAS), a web resource that contains CAS Registry Numbers for approximately 7,800 chemicals of widespread general public interest. Common Chemistry is helpful to non-chemists who know either a name or CAS Registry Number® of a common chemical and want to pair both pieces of information. The CAS Registry Number is the universally recognized unique identifier of chemical substances and is often found on packaging and on articles of commerce.

While not a comprehensive CAS Registry Number lookup service, Common Chemistry does provide a way to quickly and easily find names or CAS Registry Numbers for chemicals of general interest.

CAS has collaborated with Wikipedia in developing this resource and encourages you to use the Wikipedia link (when available) or other sources of general information on chemistry, to learn more about these chemicals.

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