how hard is the calc and chem placement tests?
By definition, a placement test is going to be pretty challenging for most kids. They want to know what you know, so they’re going to test concepts from the most basic to the very advanced, to find out where you fit on that spectrum.
No reason for stress. Just know what you know. Know the formulas, the procedures, the vocab, all the rest that you’ve been taught. And don’t worry about the material you haven’t seen yet. That’s what this test is for-- to see where that line falls between what you’ve learned and what you haven’t.