ACS Style is the standard for publications of the American Chemical Society (ACS). The emphasis is on chemistry, but the style is used in other science and engineering disciplines.
The ACS Style Guide: Effective Communication of Scientific Information. 3rd edition. is the authoritative source for how to write and cite using ACS style.
Citation Management tools let you keep track of your notes for your references and have plug-ins for word processing programs to create draft versions of your citations. For ACS style, these plug-ins are especially helpful because they will renumber your references automatically when you rearrange your paragraphs.