When I am on my Facebook account with a Gmail email address, will Gmail notify me at what time I have accessed my Facebook account?
The two are unrelated; it’s not Gmail that sends the message, but Facebook. To turn this feature on, go to Account Setting → Security → Login Notifications.
However, there is a caveat: it only works for new devices, that you haven’t used to connect to Facebook before.
We can notify you when your account is accessed from a computer or mobile device that you haven't used before