List of Polyatomic Ions
Polyatomic Ions.table
Foothill College-General Chemistry, Dr. Larson
Last Modified 12/31/08
List of Polyatomic Ions that
Must be Memorized for General Chemistry
Polyatomic Cation: NH
4
+
ammonium ion
Polyatomic Anions
Ionic Charge: -1
Ionic Charge: -2
Oxyanions:
CO
3
2–
carbonate ion
SO
4
2–
sulfate ion
SO
3
2–
sulfite ion
CrO
4
2–
chromate ion
Cr
2
O
7
2–
dichromate ion
C
2
O
4
2–
oxalate ion
S
2
O
3
2–
thiosulfate ion
Oxyanions that Contain
Hydrogen:
HPO
4
2–
hydrogen
phosphate ion
Others:
O
2
2–
peroxide ion
Ionic Charge: -3
Oxyanions:
ClO
4
–
perchlorate ion
ClO
3
–
chlorate ion
ClO
2
–
chlorite ion
ClO
–
hypochlorite ion
NO
3
–
nitrate ion
NO
2
–
nitrite ion
MnO
4
–
permanganate ion
Oxyanions that Contain
Hydrogen:
HCO
3
–
bicarbonate ion or
hydrogen carbonate ion
HSO
4
–
bisulfate ion or
hydrogen sulfate ion
H
2
PO
4
–
dihydrogen
phosphate ion
Others:
CN
–
cyanide ion
OH
–
hydroxide ion
SCN
–
thiocyanate ion
C
2
H
3
O
2
–
acetate ion
(Often written as CH
3
COO
–
)
Oxyanion:
PO
4
3–
phosphate ion
Some Notes and helpful hints:
• Some textbooks refer to oxyanions as oxoanions. These are equivalent terms, meaning
simply a polyatomic anion that consists of a central atom bonded to one or more oxygen
atoms.
• Oxyanions have names ending in –ate or –ite. The ending –ate is used for the most common
oxyanion. The ending –ite is used for an oxyanion that has the same charge, but one fewer
oxygen. The prefixes per- and hypo- are used for a series of four oxyanions of an element.
The prefix per- indicates one more oxygen than the oxyanion ending in –ate. The prefix hypo-
indicates one less oxygen than the oxyanion ending in –ite.
• When hydrogen is added to an oxyanion, it is actually an H
+
that is added thus reducing the
negative charge of the parent anion by one for each hydrogen that is added. These are
named by adding hydrogen (for one hydrogen added) or dihydrogen (for two hydrogens
added) in front of the name of the parent anion. Some of these also have common names.
For example, hydrogen carbonate ion is also called bicarbonate ion.
• Some polyatomic anions do not seem follow easy general rules regarding their names:
permanganate, chromate, dichromate, thiosulfate, oxalate, cyanide, hydroxide and acetate
are some examples.
Page 1/1
Free Download
List of Polyatomic Ions PDF
Favor this template? Just fancy it by voting!
(0 Votes)
0.0
Related Forms
