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ACS

ACS (American Chemical Society) is a numbered referencing style requiring an in-text citation within the text of your document and a related entry in a reference list at the end of your document.

Basics of referencing

This section covers in-text referencing, plus the reference list components and a sample reference list.

Format: ACS provides little formatting guidance. Check with lecturer or course outline for preferred font, size and spacing.

There are two ways to cite references within your text: superscript numbering or parenthetical numbering. 

This guide shows superscript numbering examples. Consult the manual for information on the other in-text citation.

 

Put a superscript number in your text to show when you are using another person's ideas or words. Citations are numbered consecutively in the order in which they appear in the text. The number directs the reader to the reference list, containing information about the work you are citing.  

 

When the citation applies to a whole sentence, the number appears after the punctuation. There is no space between the punctuation and the superscript number.

Example

Sensible heat is when heat is transferred to a material by raising or lowering the temperature.1 

 

Repeated references

If the reference is referred to again, the same number is used.

Example

Sensible heat is when heat is transferred to a material by raising or lowering the temperature.1 For example, when heating water on a stove from 20°C to 80°C without boiling it, the energy added is sensible heat because it's only increasing the temperature, not changing the state.1

 

Multiple works

If you are expressing ideas that have originated from more than one source, separate the numbers in ascending order and separate them with commas without spaces. A hyphen is used if referring to a range of numbers (references). 

Example

... in alkyl sulphates such as sodium lauryl sulphate.3-6,9 Other compounds showing promise were those in the C12 - C14 range.3,6,8

Reference list layout

  • Header: Add a reference list entitled References, left-aligned at the end of your essay, citing all sources used in the body of your writing.
  • Spacing: Single with an extra space between references (check with lecturer or course outline for preferred spacing). 
  • Indentation: No lines of the citation are indented.
  • Order: The reference list should be in numerical order (consecutively numbered). Each entry starts with the number followed by a full stop, a space, and then the citation.

References

1. Davies, A. G. Organotin Chemistry, 2nd ed.; Wiley-YCH: Weinheim, Germany, 2004. https://doi.org/10.1002/3527601899  

2. Boo, H. K. Students' Understandings of Chemical Bonds and the Energetics of Chemical Reactions. Journal of Research in Science Teaching 1998, 35 (5), 569-581.

3. Nielsen, A. K. Denmark: Creating a Danish Identity in Chemistry Between Pharmacy and Engineering, 1879–1914. Creating Networks in Chemistry: The Founding and Early History of Chemical Societies in Europe; Nielsen, A. K., Strbanova, S., Eds.;  Royal Society of Chemistry, 2008; pp 75-90. https://doi.org/10.1039/9781847558244-00075

4. De Mora, S. J. Chemistry of the Ocean. Principles of Environmental Chemistry; Harrison, R. M., Ed.; Royal Society of Chemistry,  2007; pp 170-233.

5. Lvovich, V. F. Distributed Impedance Models. Impedance Spectroscopy: Applications to Electrochemical and Dielectric Phenomena; Wiley, 2012; pp 97-111. https://doi.org/10.1002/9781118164075.ch6

6. Ablin, L. Engaging Students with the Real World in a Green Organic Chemistry Laboratory Group Project: A Presentation and Writing Assignment in a Laboratory Class. Journal of Chemical Education 2018, 95 (5), 817-822 (retrieved from Scopus).  https://doi.org/10.1021/acs.jchemed.7b00570 

Why we reference

When using information or ideas in your essay, research paper, dissertation or thesis, you must acknowledge and identify the original source. This is known as referencing. Whether you paraphrase, summarise or quote someone else's ideas, you must add a reference.

Referencing enables you to:

  • Avoid plagiarism
  • Allows the reader to consult the original source of your information
  • Gives evidence to your statement
  • Acknowledges the author from whom the information was obtained