What does PER Versus HYPO mean in the Beginning of Polyatomic Ion Names?
Video Explanation of PER Versus HYPO in the Beginning of Polyatomic Ion Names
Group 2 of the polyatomic ion list starts introducing us to the addition of PER and HYPO. Like ATE and ITE, PER and HYPO are a continuation of the counting of oxygens. In most cases (but not all) PER adds one more oxygen from ATE. In most cases (but not all) HYPO is minus one oxygen from ITE.
Examples: Adding Per or Hypo can changed the count of the oxygens.
IO4– | Periodate |
IO3– | Iodate |
1 | |
IO2– | Iodite |
IO– | Hypoiodite |
PRACTICE PROBLEMS: Without looking at the polyatomic ions list try to write in how many oxygen each ion has by comparing it to its neighbor above or below. The first problem is done for you as an example.
Name | Amount of Oxygen |
1 | |
Perchlorate | 4 oxygen |
Chlorate | 3 oxygen |
1 | |
Chlorite | 2 oxygen |
Hypochlorite | 1 oxygen |
1 | |
Bromite | 2 oxygen |
Hypobromite | 1 oxygen |
1 | |
Perbromate | 4 oxygen |
Bromate | 3 oxygen |