MLA Works Cited Help?

I am citing a reference book (Chemical Compounds By Neil Schlager, Jayne Weisblatt) which has 3 volumes. I am only using 1 volume; however, I am also using four different articles from that volume. When I cite this source in my Works Cited, would I cite this as just one source with its volume number, or would I do four different citations for each of the different articles that I have used from that same volume? Thanks.