Good idea to ask your teacher for extra questions as they will always be happy to help.
HSCNinja is a good place to find HSC questions although it is for the old syllabus. You can still find stuff like equilibrium and pH questions and probably more.
Try and borrow a textbook from your school or the library as they usually have chapter review questions and module questions.
Also, if you have a tutor, they can probably get you some too.