1 - Naming Polyatomic Ions:
Write names that correspond to the following formulas for polyatomic
ions: (1) PO33- (with barium ions in glass) and (2) HSO4-
CrO42- is chromate
This is one of the polyatomic ions that you would need to memorize.
PO33- is phosphite.
PO43- is phosphate, and this ion has one less
HSO4- is hydrogen
This could be called by its nonsystematic name, bisulfate, but it
is preferable to use the systematic name, which shows that one H+
ion has been added to sulfate, SO42-.
2 - Formulas for Polyatomic Ions:
Write formulas that correspond to the following names for
polyatomic ions: (1) bromite ion, used in the production of cloth and (2) dihydrogen hypophosphite ion, used with
manganese(II) ions as a food
Bromite ion is BrO2-. Bromate is BrO3-.
Bromite has one less oxygen atom than bromate.
Dihydrogen hypophosphite ion is H2PO2-.
Hypophosphite has two less oxygen atoms than phosphate, PO43-.
The dihydrogen part of the name indicates that two H+ ions have
been added to hypophosphite, PO23-.
The two H+ ions neutralize two of the three minus
charges, leaving -1.
here to see a sample exercise.
here to convert oxyanion formulas to names. (Requires the Java Plug-in.)
Return to the Oxyanions Nomenclature Page.