I would NEVER suggest using a violent act as a way to deter a child from a violent act. It sends HUGE mixed signals... don't hit mommy, but mommy can hit you. Ultimately you are trying to teach her not to use physical violence to get her way, which is the exact thing that you are doing.Your daughter doesn't have a bad attitude she is exploring social boundaries and new emotions. Her emotions are more complex, as are her thoughts, yet she lacks the verbal skills to communicate what she wants. The first step is to try and head off the temper tantrum before it happens. She is expressing frustration over something so find out what she wants before she reaches her boiling point. I am not suggesting you find out what she wants and give it to her. Find out so you can address the real problem.Before she hits her boiling point ask her calmly (the way you would want an adult to talk to you) what is is that she wants, or is feeling. You might need to help her figure it out. If she boils over let her know what you really want to help her but you can't until she is calm. You aren't telling her to calm down, let her get it out of her system. Then afterwards talk to her.You are the adult, if she tries to hit or scratch just calmly remove yourself from the situation. Don't react, interact, or feed into it. She wants you to engage her, if you engage you are giving her one of the things that she wants (rewarding the behavior you don't like).When you change her diaper explain to her what you are going to do, what you are doing, and why. Ask her to help (even if helping is just being still). If she is still kicking and screaming after you get her cleaned up let her. I am guessing she is trying to exert some kind of independence. Rather than fighter her figure out a way to help her feel independent.