不平分子-Fuheibunshi-Malcontent. Bunshi is also "molecule".
I've always been a malcontent. Recently I realized what a drag it is to be around people like that, er, me. When a teacher explained an assignment, it was a matter of seconds until I was griping to myself about how stupid it was. Of course, my disdain came across to my classmates (usually team members) and probably to my teachers.
When I teach here, I have kids who act like this. I am embarrassed that I behaved like this as an adult.