Skip to Main Content

University of Portland Clark Library

CHM 277: General Chemistry: Citing Sources

American Chemical Society (ACS) Style

Common ACS Examples for UP Students

For detailed style guidelines see: Chapter Data & Datasets

For an online book or encyclopedia:

Cyclohexane. In CRC Handbook of Chemistry and Physics, 104th ed.; Rumble, J. R., Ed.; CRC Press, 2023. (accessed 2023-08-19). (CAS RN: 110-82-7).

For an online database:

Cyclohexane. The Merck Index Online. Royal Society of Chemistry, 2013. (accessed 2023-08-15). (CAS RN: 110-82-7).

Cyclohexane. SDBSWeb. National Institute of Advanced Industrial Science and Technology, n.d. (accessed 2023-08-17). (CAS RN: 110-82-7).

Cyclohexane. SciFinder. CAS, n.d. (accessed 2023-03-28). IR spectral data obtained from Bio-Rad Laboratories. (CAS RN: 110-82-7).

For detailed style guidelines see: Chapter Safety Data Sheets

Found through a third-party such as University of Portland MSDS Online:

Cyclohexane; CAS RN: 110-82-7; 650455; ver. 6.8; Sigma-Aldrich: St. Louis, MO, May 25, 2023. Retrieved from University of Portland MSDS Online. (accessed 2023-08-15).

Found on manufacturer site:

Cyclohexane; CAS RN: 110-82-7; 227048; ver. 6.9; Sigma-Aldrich: St. Louis, MO, May 24, 2023. (accessed 2023-08-15).

Citing an experiment or appendix from the course lab manual? Use the ACS format for citing a chapter in a book.


Bard, R.; Bard, R.; Breuer, K.; Jacob, W.; Osborne, D.; Schacherer, L.; Taylor, B.; Thompson, W.; Valente, E.; Wood, W. Experiment A2: Distillation of a Mixture of Cyclohexane and Toluene. In CHM 375 Organic Chemistry I Laboratory Manual; University of Portland, 2023-2024; pp 25-32.

The Chemical Abstracts Service (CAS) Registry has 204 million organic and inorganic substances. Each substance has been given a unique registry number (RN) and that is the most accurate way to search for information about it. Searching by substance name can be less accurate since there are different naming systems.

The registry number might be referred to as:

CAS Registry Number
CAS Number

The number has dashes which are considered part of the number. For example, the CAS RN for Cyclohexane is: 110-82-7. Include the dashes when searching by CAS RN in various databases, and also when including the number in a citation for a source. 

APA Style (7th ed.) - UP Library Help | 503.943.7111 or 800.841.8261 | 5000 N. Willamette Blvd., Portland, OR 97203-5798
Copyright © University of Portland, All Rights Reserved | Icons made by Freepik from