@vortex275 Math 1 covers less advanced concepts, and many colleges ask that if you take a math SAT II, you take Math 2. Also, the curve is extremely harsh (you need a perfect raw score to get an 800) on Math 1, while it is much more lax for Math 2.
Are pre-IB courses like Honors courses? If so, you can take the SAT II Chemistry this year. I’m taking it after Honors Chem.