High Quality Content by WIKIPEDIA articles! The American Chemical Society (ACS) is a scientific society based in the United States that supports scientific inquiry in the field of chemistry. Founded in 1876 at New York University, the ACS currently has more than 161,000 members at all degree-levels and in all fields of chemistry, chemical engineering, and related fields. It is the world`s largest scientific society and one of the leading sources of authoritative scientific information.