You may know a lot about chemistry man, but you don’t know jack about slangin’ dope.

Walt: Last time I checked, there was 16 ounces to a pound. What’d you do with the rest, smoke it?
Jesse: Yo, I been out there all night slangin’ crystal. You think it’s cake movin’ a pound of meth one tenth at a time?
Walt: So why you selling it in such small quantities? Why don’t you just sell the whole pound at once?
Jesse: To who? What do I look like? ‘Scarface?’
Walt: This is unacceptable. I am breaking the law here. This return is too little for the risk. I thought you’d be ready for another pound today.
Jesse: You may know a lot about chemistry man, but you don’t know jack about slangin’ dope.