How can I memorize the polyatomic ions? Is there an acronym?
Agreeing with the other answer, there is no acronym.
However, for the -ates, -ites, per -ates, and hypo -ites, you can memorize the base form (the -ate) and derive the others.
For example, if you know that Phosphate is
For the Perphosphate form, you add one Oxygen to the phosphate form (
Notice how all of these have the same charge, just a differing number of Oxygen atoms.
As for memorizing the base forms, there is a trick I use. If you have a periodic table available, you can use this trick:
For columns 5 & 6, there will be 4 Oxygens in the -ate form (with the exception of Nitrate (
For column 7, there will be 3 Oxygens in the -ate form.
For column 7, the charge is always -1, for column 6 it's -2, and for column 5 it's -3.
This all looks super complicated written out, but put it on the table and it's easy to memorize.
Best of luck.