Scientific Tutor

What are polyatomic ions?

In the previous section of ions we looked at how ions could be created from a single atom of a single element. There are, however, ions that are made up of many different atoms bonded together. These are what we call the polyatomic ions. If you break down the word, poly means “many” and atomic means “atoms”.  I designed several of the sections after this one to help you understand the polyatomic ions better.  The polyatomic ion sections also help you find tricks to more easy memorize the polyatomic ions if needed.

Why are polyatomic ions important?

We interact with polyatomic ions all the time without realizing it.  They are in the soil and streams and they are critical components to all life forms.  Some of them are the nutrients that make up the components of all living things body.   For example, phosphate is critical for farmers to spread in the field as part of fertilizer.  At the same time phosphate makes up part of our blood, our bones, and our DNA.

Do I need to memorize the polyatomic ions?

YOU CAN LOOK AT THE POLYATOMIC ION LIST IN THE PICTURE BELOW OR IN THIS LINK. Whether or not you need to memorize the polyatomic ions will depend mostly on what kind of chemistry class you are in.  In most general chemistry high school classes, you do not need to memorize them.  However, honors high school classes may make you memorize a small number of these polyatomic ions but AP and college classes will make you memorize most of them.

What do I need to know or memorize about the polyatomic ions?

What you have to know is the name, chemical formula, and charge of everything in the polyatomic ion list below.  I ranked the following polyatomic ions into groups. Group 1 you absolutely have to know how to spot or memorize and you will see them very often. Group 2 would be useful to know, but not critical. Some of the Group 3 polyatomic ions will be used in AP and college students. While you are reading through and learning this chapter you should always have the polyatomic ions link open so you can look back at it. All other sections in this lesson are just to help you understand the names of the polyatomic ions and to help you memorize them. If you know how to memorize them on your own then you don’t need to look at any more sections. However, I strongly suggest that you do continue with the rest of the sections.