I think I am going to wash my mom's car, but use acid and liquid nitrogen instead of soap.
Why would you wash her car with that?
It is a way to protest.
Caring about the environment can be good but you shouldn't do things that hurt others in order to protest. You could get grounded or kicked out of your home. You should just make a sign and go protest somewhere else.
I think it will be a great symbol.
Doing something to protest for the environment at the expense of your mother's car is pretty messed up. You should use one of your items instead in case things go wrong. You are simply harming your mother by doing this.