You would only reference chapters separately if they were written by different authors. This is what is referred to as an edited book. There is a theme to to the chapters, an editor or group of editors who select and edit the chapters, and then the individuals who write the chapters. If this was the case, each chapter would have a different author and the citations would be arranged alphabetically by author in your reference list.

However, since you only have one author, you would treat this a regular book. Chapters do not matter.