Symbols and Charges for Monatomic Ions
Fixed Charge
Symbol
Name
Symbol
Name
H1+
hydrogen ion
H1-
hydride
Li1+
lithium ion
F1-
fluoride
Na1+
sodium ion
Cl1-
chloride
K1+
potassium ion
Br1-
bromide
Rb1+
rubidium ion
I1-
iodide
Cs1+
cesium ion
O2-
oxide
Be2+
beryllium ion
S2-
sulfide
Mg2+
Magnesium ion
Se2-
selenide
Ca2+
calcium ion
Te2-
telluride
Sr2+
strontium ion
N3-
nitride
Ba2+
barium ion
P3-
phosphide
Ra2+
radium ion
As3-
arsenide
Al3+
aluminum ion
The ending for a negative ion’s name is –ide.
For example, fluorine is fluoride. Replace the -ine with -ide
Ag1+
silver ion
Zn2+
zinc ion
Symbols and Charges for Monoatomic Ions
Variable Charge
Symbol
(Stock system)
Systematic name
Common name
Symbol
(Stock system)
Systematic name
Common name
Cu+
copper(I)
cuprous
Ni2+
Nickel(II)
nickelous
Cu2+
copper(II)
cupric
Ni4+
Nickel(IV)
nickelic
Au+
gold(I)
aurous
Sn2+
tin(II)
stannous
Au3+
gold(III)
auric
Sn4+
tin(IV)
stannic
Cr2+
chromium(II)
chromous
Pb2+
lead(II)
plumbous
Cr3+
chromium(III)
Chromic
Pb4+
lead(IV)
plumbic
Mn2+
manganese(II)
manganous
Mn3+
manganese(III)
manganic
Fe2+
iron(II)
Ferrous
Hg22+
mercury(I)
mercurous
Fe3+
iron(III)
Ferric
Hg2+
mercury(II)
mercuric
Co2+
cobalt(II)
cobaltous
Co3+
cobalt(III)
Cobaltic
Symbols and Charges for Polyatomic Ions
Formula
Name
Formula
Name
ClO31-
Chlorate
NO31-
Nitrate
ClO21-
Chlorite
NO21-
Nitrite
ClO1-
Hypochlorite
IO41-
periodate
ClO41-
Perchlorate
IO31-
Iodate
PO43-
Phosphate
IO1-
hypoiodite
PO33-
Phosphate
CO32-
carbonate
HPO42-
hydrogen phosphate
HCO31-
hydrogen carbonate or bicarbonate
H2PO41-
dihydrogen phosphate
BrO31-
Bromate
SO32-
Sulfite
BrO-
hypobromite
SO42-
Sulfate
HC2O41-
hydrogen oxalate or binoxalate
HSO41-
hydrogen sulfate or bisulfate
CN1-
Cyanide
HSO31-
hydrogen sulfite or bisulfite
HS1-
Hydrogen sulfide
CrO42-
Chromate
S2O32-
thiosulfate
Cr2O72-
Dichromate
AsO43-
Arsenate
MnO41-
Permanganate
O22-
Peroxide
OH1-
Hydroxide
NH21-
Amide
BO33-
Borate
B4O72-
Tetraborate
NH4+
ammonium
The polyatomic ions below do not have to be memorized, but you will encounter them.
C2O42-
Oxalate
C4H4O62-
Tartrate
SCN1-
thiocyanate
SeO42-
selenate
C2H3O21- (CH3COO1-)
Acetate
SiO32-
silicate
SiF62-
hexafluorosilicate