INORGANIC NOMENCLATURE REFERENCE SHEET
Determine if the first element in the formula is a metal, nonmetal, or hydrogen.
1. If the first element is a metal (or the ammonium ion) go to section I.
2. If the first element is a nonmetal go to section II.
3. If the first element is hydrogen go to section III.
I.
METALS with NONMETALS ( or negative polyatomic radicals): (IONIC COMPOUNDS
– smallest representative unit is the formula unit – transfers electrons)
A. Determine if the first element is monovalent or multivalent. Look at the periodic table and
determine if there is only one valence listed in the oxidation state (monovalent) or if there
are more that one valence listed in the oxidation state (multivalent).
B, MONOVALENT metals are named by stating the name of the metal followed by the
name of the negative ion or polyatomic ion. Formulas are written from names by writing
cation and anion formulas with charges and “crisscrossing” the charges. Reduce to LCD.
EXAMPLES:
CaCl2
CaSO4
Al(OH)3
calcium chloride
Ca 2+
calcium sulfate
aluminum hydroxide
Cl
2
1-
C. MULTIVALENT metals are named by stating the name of the metal followed by a Roman
Numeral which represents the valent state (charge) of the metal, and lastly, naming the
negative ion or polyatomic ion. The Roman Numeral does not indicate the number of atoms
of that element. Formulas are written from names by writing cation and anion formulas with
charges and “crisscrossing” the charges. Reduce subscripts to LCD.
EXAMPLES:
EXAMPLE: Cu(NO3)2
Answer: Copper (II) nitrate
The “-1” = no. of“Cu”.
The “2” = no. of “NO3”
II.
FeCl2
FeCl3
Cr2(SO4)3
Mo(OH)6
2
-1
Cu (NO3)2
+2
iron (II) chloride
iron (III) chloride
chromium (III) sulfate
molybdenum (VI) hydroxide
EXAMPLE: Iron (III) sulfate
Fe3+
SO4-2
Answer: Fe2(SO4)3
2
6
3
-2
NONMETALS WITH NONMETALS (COVALENT/MOLECULAR COMPOUND –
smallest representative unit is the molecule – shares electrons)
A. Indicate the number of atoms of each element by using the prefixes di-, tri-, tetra-, penta-, etc. If
there is only one atom of the first element in the formula, the mon- prefix is usually omitted.
MEMORIZE THESE PREFIXES:
1 = mon6 = hex(a)-
2 = di7 = hept(a)-
EXAMPLES
P2O5
CO2
P4O10
CO
3 = tri8 = oct(a)-
4 = tetra9 = non(a)-
5 = penta10 = dec(a)-
diphosphorus pentoxide or diphosphorus pentaoxide
carbon dioxide(notice the mon- prefix is not used)
tetraphosphorus decaoxide
carbon monoxide
(the mon- prefix is used for CO)
III.
HYDROGEN IS THE FIRST ELEMENT:
A. Hydrogen is monovalent, thus, is could be named like a monovalent metal.
EXAMPLES:
HCl
HNO3
HC2H3O2
hydrogen chloride
hydrogen nitrate
hydrogen acetate
B. When hydrogen containing compounds are put into water they become acids and have a naming
system of their own. The hydrogen ion, H+, in water is the general definition for an acid.
Any of the following substances dissolved in water yields hydrogen ions, and is thus, an acid.
This will be discussed during the chapter on acids and bases. At this time memorize the
following acids.
HCl
HNO3
H2SO4
HC2H3O2
H3PO4
hydrochloric acid
nitric acid
sulfuric acid
acetic acid
phosphoric acid
HNO2
H2SO3
H2CO3
H3PO3
nitrous acid
sulfurous acid
carbonic acid
phosphorous acid
IV. MISCELLANEOUS COMPOUNDS: The following names are without reason or commonly used
compounds:
NH3
CH4
ammonia
methane
H2O water
H2O2 hydrogen peroxide
V. MEMORIZE THIS TABLE OF COMMON IONS:
acetate
bromide
carbide
carbonate
hydrogen carbonate
or bicarbonate
chlorate
chlorite
hypochlorite
chloride
chromate
dichromate
cyanide
fluoride
hydroxide
iodide
iodate
nitrate
nitrite
nitride
oxalate
oxide
peroxide
CATION:
C2H3O21Br1C4CO32-
perchlorate
permanganate
phosphide
phosphate
phosphite
monohydrogen phosphate
dihydrogen phosphate
azide
sulfate
sulfite
hydrogen sulfate
or bisulfate
hydrogen sulfite
or busulfite
sulfide
HCO31ClO31ClO21ClO1Cl1CrO42Cr2O72CN1F1OH1I1IO31NO31NO21N3C2O42O2O22-
AMMONIUM
hydrogen sulfide
or bisulfide
silicate
thiosulfate
thiocyanate
or thiocyanide
NH41+
ClO41MnO41P3PO43PO33HPO42H2PO41N31SO42SO32HSO41HSO31S2HS1SiO32S2O32SCN1-
(behaves like a monovalent metal)