Zotero is the best choice for Mac users. It also plays nicely with PC's.
At https://www.Zotero.org/download/, click to download BOTH Zotero AND the Zotero Connector. You need both tools, working together:
Click the download arrow for the article in question:
Then, under "Download Reference Details," choose "Citation (.ris)."
It should go directly to the Zotero app, where you can choose where to file it.
First, add American Chemical Society (ACS) citation style (see ACS style box to the left in this guide).
Within Word, to add a citation or Bibliography, click the Zotero button, and you can choose how to proceed:
When it gives you the option of Citation styles, choose "American Chemical Society":
In ONESearch, click on Export .RIS to save the file:
Click the green button to download:
When you click on the file, it should automatically open Zotero and dump in your citation for you.
To export a citation from Google Scholar or another website to Zotero, click the button in the far right corner of your browser (circled here):
