<p>I too disagree that ap chem is necesarry to get a respectable score on this test. Also, if you got a 550 without any review at all, then I don’t think you’re in an enormous amount of trouble because for me, I know review was absolutely essential. My school doesn’t give finals, and I had completely forgotten a lot of concepts. It might be tough with little time remaining (though with good time management it doesn’t have to be), but I would carefully go through the review section of a prep book (you could use sparknotes’ free, online one), and then about 4 days before the test, do one practice test a day for the next 3 days, so you can brush up on things you might not have absorbed well from the book. You may hear this a lot, but it’s important when reviewing your practice tests to try and fully understand why you missed a question so you’ll never make the same mistake again, because with the consistency of subject tests, chances are you will run into that concept on the test day. Good luck.</p>