How do I in-text reference a book chapter as a whole, without citing specific text in APA style?

If you are referring to the whole chapter or paraphrasing a section, the reference will simply be (Corey, 2016).  No page number is required in this instance but you can include one when paraphrasing from a specific page to help the reader locate the relevant passage.

If you are directly quoting from the chapter you need to include the page number (Corey, 2016, p. 141).  The chapter number is never required.

Sometimes each chapter has a different author, as well as an editor for the entire book. In this case, you would reference the author of the chapter in the text. For more information, see the Chapter in an edited book section of the Books page in the APA Guide, or follow the link below.