NOMENCLATURE OF INORGANIC CHEMICAL COMPOUNDS
OXIDES
Binary compounds containing oxygen
TRADITIONAL NOMENCLATURE
IUPAC NOMENCLATURE
There are 3 classes of oxides: alkaline oxides, acid oxides and peroxides.
1. Alkaline oxides: formed by a metal and oxygen with general
formula
+x
-2
Me2Ox
• If a metal has only 1 O.N. (oxidation number) the name of the
compound is: NAME OF METAL + “OXIDE”
No distinction is made between alkaline and acid oxides. The name
of the compound is: NAME OF THE ELEMENT BONDED TO OXYGEN
+ “OXIDE”
Prefixes are used to indicate the number of atoms.
• If a metal has 2 O.N.
→ the lowest O.N. takes suffix -OUS
→ the highest O.N. takes suffix -IC
+1 -2
Examples: Na2O sodium oxide
+1 -2
Examples: Na2O disodium oxide
+1 -2
+1 -2
Cu2O cuprous oxide
Cu2O dicopper oxide or copper (I) oxide
+2 -2
+2 -2
CuO cupric oxide
CuO copper oxide or copper (II) oxide
2.
Acid oxides or anhydrides: formed by a non-metal and oxygen with
general formula
+y -2
X2Oy
• If a non-metal has only 1 O.N., the name of the compound is: NONMETAL with suffix -IC + “ANHYDRIDE”
+4 -2
Example: SiO2 Silicic anhydride
• If a non-metal has 2 O.N.
→ the lowest O.N. takes suffix -OUS
→ the highest O.N. takes suffix -IC
+3 -2
Examples: N2O3 Nitrous anhydride
+5 -2
+4 -2
Example: SiO2 Silicic dioxide
+3 -2
Examples: N2O3 Nitrous anhydride or nitrogen (III) oxide
+5 -2
N2O5 Nitric anhydride or nitrogen (V) oxide
N2O5 Nitric anhydride
• If a metal has more than 2 O.N.
→ the lowest O.N. also takes prefix -HYPO
→ the highest O.N. also takes prefix -PER
+1 -2
Examples: Cl2O hypochlorous anhydride
+3 -2
+3 -2
Cl2O3 chlorous anhydride
Cl2O3 dichloric trioxide
+5 -2
+5 -2
Cl2O5 chloric anhydride
Cl2O5 dichloric pentoxide
+5 -2
Cl2O7 perchloric anhydride
3.
+1 -2
Examples: Cl2O dichloric oxide
+5 -2
Cl2O7 dichloric eptoxide
Peroxides: compounds that contain 2 oxygen atoms bonded to
each other (oxygen in this case has N.O. -1)
Their name is: NAME OF METAL + “PEROXIDE”
+1 -1
Examples: H2O2 hydrogen peroxide
+2 -1
BaO2 barium peroxide
+1 -1
Examples: H2O2 hydrogen peroxide
+2 -1
BaO2 barium peroxide
HYDROXIDES
Ternary compounds containing a metal, oxygen and hydrogen (OH)
+x
-1
General formula: Me(OH)x
OH group has a total O.N. of -1 and it’s called hydroxide ion.
Hydroxides are obtained from the reaction between alkaline oxides with H2O.
TRADITIONAL NOMENCLATURE
IUPAC NOMENCLATURE
Their name is: NAME OF METAL + “HYDROXIDE”
• If a metal has 2 O.N.
→ the lowest O.N. takes suffix -OUS
→ the highest O.N. takes suffix -IC
+2
+2
-1
Examples: Mg(OH)2 magnesium hydroxide
+1
+2
+1
-1
HgOH
-1
Examples: Mg(OH)2 magnesium dihydroxide
-1
HgOH
mercurious hydroxide
+2
-1
mercury hydroxide
-1
Hg(OH)2 mercury dihydroxide
Hg(OH)2 mercuric hydroxide
OXYACIDS
General formula: HXO
Oxyacids are ternary compounds containing hydrogen (H), a non-metal and oxygen (O). They are obtained from the
reaction between anhydrides/acid oxides with H2O.
TRADITIONAL NOMENCLATURE
IUPAC NOMENCLATURE
Their name is: NAME OF ANHYDRIDE + “ACID”
The name is: PREFIX which specifies the number of oxygen
atoms in the compound (monoxo/dioxo/trioxo…) + NAME OF
NON-METAL (with IC suffix) + ACID + O.N of non metal in
roman number
+4
Examples: SO2 + H2O → H2SO3 sulfurous acid
+6
SO3 + H2O → H2SO4 sulfuric acid
+4
Examples: SO2 + H2O → H2SO3 trioxosulfuric acid (IV)
Anhydrides of some non-metals (P, As, Sb, B, Si) can react with
more than one water molecule, producing different types of acids:
Anhydride + 1 H2O → META acid
Anhydride + 2 H2O → PIRO acid
Anhydride + 3 H2O → ORTO acid
Examples: P2O5 + 1 H2O → H2P2O6 → HPO3
metaphosphoric acid
P2O5 + 2 H2O → H4P2O7
pirophosphoric acid
P2O5 + 3 H2O → H6P2O8 → H3PO4
orthophosphoric acid
Exception: ortosilicic acid is obtained by adding 2 molecules of H2O
to silicic anhydride:
SiO2 + 2 H2O → H4SiO4
orthosilicic acid
+6
SO3 + H2O → H2SO4 tetroxosulfuric acid (VI)
BINARY COMPOUNDS CONTAINING HYDROGEN
TRADITIONAL NOMENCLATURE
IUPAC NOMENCLATURE
There are 3 classes of binary compounds containing hydrogen: metal
hydride, hydracids and covalent hydrides.
No distinction is made between hydrides and hydracids.
The name of the compound is given by adding suffix -IDE to the
element on the right of the chemical formula, followed by the
name of the other element.
1.
Metal hydrides: formed by a metal and hydrogen with general
formula
+x -1
MeHx
In hydrides, hydrogen always has O.N. -1
Prefixes di-, tri-, tetra- are used to indicate the number of atoms in
the formula.
• If a metal has only 1 O.N. (oxidation number) the name of the
compound is: NAME OF METAL + “HYDRIDE”
• If a metal has 2 O.N.
→ the lowest O.N. takes suffix -OUS
→ the highest O.N. takes suffix -IC
+1 -1
Examples: NaH sodium hydride
2.
+1 -1
Examples: NaH sodium hydride
+1 -1
+1 -1
CuH cuprous hydride
CuH cupric hydride
+2 -1
+2 -1
CuH2 cupric hydride
CuH2 cuprc dihydride
Hydracids: formed by hydrogen and some non-metal with general
formula
+1 y
Hy X
The name is NON METAL with prefix HYDRO and suffix -IC + “ACID”
Examples:
HF hydrofluoric acid
HCl hydrochloric acid
HBr hydrobromic acid
HI hydroiodic acid
H2S hydrosulfuric acid
HCN hydrocianic acid
3.
Examples:
HF hydrogen fluoride
HCl hydrogen chloride
HBr hydrogen bromide
HI
hydrogen iodide
H2S hydrogen sulfide
HCN hydrogen cyanide
Covalent hydrides: formed by hydrogen and some non-metal or
semimetal. These compound are called with common names:
Examples:
CH4 methane
SiH4 silane
NH3 ammonia
PH3 phosphine
AsH3 arsine
Examples:
CH4 carbon tetrahydride
SiH4 silicon tetrahydride
NH3 nitrogen trihydride
PH3 phosphorous trihydride
AsH3 arsenicum trihydride
SALTS
+x
-y
General formula: Mey(AR)x
where AR is the acid residue
Compounds that originate from acids (oxyacids or hydracids) where hydrogen atoms (of the acid) have been
substituted by metal atoms.
Salts are named after their corresponding acids, both In IUPAC and TRADITIONAL nomenclature.
TRADITIONAL NOMENCLATURE
IUPAC NOMENCLATURE
The acid residue (atomic group which is left after 1 or more H atoms
are removed from an acid) has negative O.N. equal to the number of
missing hydrogens.
+1
-2
Salt from hydracid: the name of the compound is: NAME OF
METAL with the prefix indicating the number of metal atoms +
NAME OF NON METAL with suffix -IDE.
H2SO4 → - 2H → (SO4)
+3 -2
The name of the salt is taken from the corresponding acid, with varying
prefixes and suffixes according to the following scheme:
Examples: Fe2S3 iron(III) sulphide or diiron trisulphide
+2 -1
FeCl2 iron(II) chloride or iron dichloride
From hydracid
(binary compound)
From oxyacids
(ternary compound)
Acid
-idric
Hypo-ous
-ic
Per-
Salt
-ide
-ous
-ic
Hypo-ite
-ate
Per-
-ite
Salt from oxyacid: the name of the compound is: NAME OF METAL
with the prefix indicating the number of metal atoms + NAME OF
NON METAL with suffix -ATE.
-ate
If the metal has more than one O.N:. then the oxidation number is
added in brackets in roman numbers. Ù
+2
The name of the metal comes before.
+1
• If a metal has only 1 O.N. (oxidation number) the name of the
compound is: NAME OF METAL + NAME OF THE ACID RESIDUE
• If a metal has 2 O.N., the name of the metal varies according to:
→ the lowest O.N. takes suffix -OUS
→ the highest O.N. takes suffix -IC
+3 -2
Examples: Fe2S3 ferric sulphide (from H2S)
+2
-1
Ca(ClO4)2 calcium perchlorate (from HClO4)
Acids that have more than one H atoms on the molecule can form
different types of acid residues according to the number of H atoms
present.
+1
-1
H3PO4 → -1H → (H2PO4) AR biacid
+1
-2
→ -2H → (HPO4) AR monoacid
+1
-3
→ -3H → (PO4)
+1
AR neutral
-1
Example: Na(HCO3) sodium hydrogen carbonate (from H2CO3)
-1
Examples: Ca(ClO4)2 calcium tetraoxochlorate (VII)
-2
Na2CO3 sodium carbonate or disodium trioxocarbonate
TABLE OF THE MOST COMMON IONS
Positive ions (cations)
Name
Aluminium
Ammonium
Barium
Cadmium
Calcium
Chrome II
Chrome III
Cobalt II
Cobalt III
Copper I
Copper II
Gold I
Gold III
Iron II
Iron III
Lithium
Lead II
Lead IV
Magnesium
Manganese II
Manganese III
Mercury I
Mercury II
Nickel
Platinum
Potassium
Silver
Sodium
Strontium
Tin II
Tin IV
Zinc
Formula
Al3+
NH4+
Ba2+
Cd2+
Ca2+
Cr2+
Cr3+
Co2+
Co3+
Cu+
Cu2+
Au+
Au3+
Fe2+
Fe3+
Li+
Pb2+
Pb4+
Mg2+
Mn2+
Mn3+
Hg+
Hg2+
Ni+
Pt2+
K+
Ag+
Na+
Sr2+
Sn2+
Sn4+
Zr2+
Negative ions (anions)
Name
Acetate
Borate
Bromate
Bromide
Carbonate
Carbonate (acid), Bicarbonate
Cyanide
Chlorate
Chlorite
Chloride
Chromate
Dichromate
Fluoride
Hydroxide
Hydride
Hypochlorite
Iodide
Manganate
Nitrate
Nitrite
Oxalate
Perchlorate
Permanganate
Phosphate
Phosphate acid
Phosphite
Sulfate
Sulfate acid, Bisulfate
Sulfite
Sulfite acid, Bisulfite
Sulfide
Thiocyanate
Thiosulfate
Formula
CH3COOBO33BrO3Br CO32HCO3CNClO3ClO2ClCrO42Cr2O72FOHHClOIMnO42NO3NO2C2O42ClO4MnO4PO43HPO42PO33SO42HSO4SO32HSO3S2SCNS2O32-