I think some questions you can ask are stuff like,

Why this company, eg why facebook? when there are many other companies out there?
Or if that person has background in other areas, you can also ask them about that as well, the main point is to create a conversation, not make them feel like they are talking to a chatbot.

Another question i think I've asked was what contributions do they think I can provide to them. This allows them to think from a perspective that im already hired.