There is a lot of information on the web about spotting fake Facebook profiles. While you're sure to learn more on the job, make sure you're well-versed on this topic before the interview.

"There are a number of ways to spot fake accounts on Facebook. For example, the profile picture is a good indicator. If there's no profile picture or just one picture that hasn't been changed in years, that's a red flag. An empty "About" section is another red flag, as is having a different name in the URL than what's shown in the profile."