Corwin’s Ion Flowchart-Chapter 7



From Chapter 7 Corwin (Chapter 5 Hill), Monoatomic Anions or Cations can be predicted the position the element resides on the periodic chart, if the ion come from a Representative Element (IA-VIIIA) or by its name if it is a transitional metal with several different charges. Below is Corwin Figure 7.3 demonstrating common cations and anions:

                              Periodic Table of Selected Ions


Note the charges for groups IA, IIA, IIIA, VA, VIA, VIIIA. From book to book, the charges on the transitional metals will vary


You should practice: M-3 Part F, then try M-4 Part D and write the formulas for Binary Ionic Compounds. Sections 7.4 and 7.5 of the Corwin text describes the process. Then you should try the web site for homework points Naming Binary Ionic Compounds:;

You should practice Questions #25-#34 at the end of Chapter 7 for more practice.

Almost all chemistry textbooks have sections dedicated to polyatomic ions and include a list of common ions. Corwin suggests that you use flash cards listing the name on one side and the formula with its charge on the other to aide your memorization of these formulas. Most chemistry teachers require you to know some of the common polyatomic ions by the end of the course whether it is from repetition of use with a help table or from memory from the first day of introduction. Below are tables from various chemistry books used on the North campus:


Polyatomic Ion Charts from Textbooks
Table 3.2    Corwin: Table 7.03
Table 2.5     Tillery: Table 9.3
Table 3.1      Hill:     Table 5.04


Here is a sample polyatomic ion table:

Hill’s Table 5.4 (and Hill suggest for you to memorize the entire table):

 After you start memorizing, the rest of the course the formulas will be swimming in you head and the charges. To write balance Ternary Ionic Compounds, you must be able to write the formula and the charge of each polyatomic ion required.

Corwin suggests there is only one (Hill has two) common polyatomic Cation(s) and both end in ium suffix. He notes most of the Anions have an –ate suffix, while a few have ite, and two have ide in their name. How do we accomplish this list?


Knowing dot structures of polyatomic ions (Corwin Chapter 12 section 12.5), and some keen observations you can boil it down to four questions:

Knowing dot structures of polyatomic ions (Corwin Chapter 12 section 12.5), and some keen observations you can boil it down to six questions:

1.    What is the formula for the –ate polyatomic ion?

2.    What is the charge on –ate polyatomic ion?

3.    What happens when you attach hydrogen atom(s) to the polyatomic

     2- and 3- anions?

4. What does ite mean?

5.    How do the hypo- and per- prefixes apply to polyatomic ions?

6.    What are the two ide polyatomic ions and two -ium positive Anions?

So: it is time for you to discover, what I saw over 50 years ago. It is not in any textbook. The books just say know or memorize these tables. Go to: