It's more likely to be an issue with the FaceBook app itself. Or it maybe those particular images are not compatible with the iPad (unlikely as that is). There really isn't anything you can do in the iPad's settings that will affect FaceBook's ability to display images, however the iPad is compatible with fewer image file types than your Mac.
You can also try visiting FaceBook in Safari on the iPad and see if the images fail to display properly there. If they don't, then it may be that 'unlikely' image compatibility issue after all. If the images are from the same source, that would also indicate a possible file compatibility problem.
What you can do:
If a restart or reset don't clear up the problem I'd try deleting and re-installing the FaceBook app. The FaceBook updates every couple of weeks, so this would make sure you have the newest version, and that it hasn't been corrupted by a failed update.
Restart: Hold down the power button until the Power Off slider appears, and slide it off. Wait until the iPad finishes shutting down, then hold down the power button for a few seconds to turn it back on.
Reset: Hold down the power and home buttons until the Apple logo appears. The iPad will restart on it's own.