Chem 111/121 9/29/02
Nomenclature Worksheet 5
A. The ‘ite’ Oxo anions
The ‘ite’ anions are formed from the ‘ate’ anions by removing one oxygen.
The charge does not change. Not all the ‘ate’ anions have ‘ite’ counterparts.
NO 2 nitrite
ClO 2- chlorite
SO 32- sulfite
PO 3 phosphite
B. The ‘per’ and ‘hypo’ Oxo anions
Some elements are able to combine with oxygen and form a range of oxo anions.
When this happens the prefix of the anion changes.
If there is one MORE oxygen than the ‘ate’ anion, use the prefix per.
ClO 4- perchlorate
If th-re is one LESS oxygen than the ‘ite’ anion, use the prefix hypo.
C. More polyatomic ions
NH 4+ ammonium cation (note: the only nonmetal cation we will use)
CN - cyanide
HCO 3- hydrogen ca