1. Nomenclature of Inorganic Chemistry
1. Elements & oxidation
numbers
2. Types of nomenclature
3. Ions
4. Binary compounds
1. Hydrides
2. Oxides
3. Peroxides
4. Binary salts
5. Hydroxides
6. Oxoacids
7. Oxosalts
8. Acid salts
Patricio Gómez Lesarri

2. 1. Elements & oxidation numbers
 An element is any chemical
substance which consists of
just one type of atom.
 Chemical elements are
ordered in the periodic table
according to their atomic
number.
 Each column, which is called
group, has elements of
simmilar chemical properties.

3. 1. Elements & oxidation numbers
 Oxidation number: electric
charge that an element has when
it is combined
 Valence: Ability to bind to a
certain number of atoms
 Atoms try to get a full valence
shell, in other words, 8 electrons
in the outer shell
 Metals: elements which tend to
lose electrons, so they become
positive
 Nonmetals: elements which
tend to gain electrons, so they
become negative
 Noble gases: stable elements,
which don´t combine
Valence Elements
1 Group 1 (Lithium, Sodium,
Potassium, Rubidium, Caesium) &
Silver
2 Group 2 (Beryllium, Magnesium,
Calcium, Strontium, Barium,), Zinc
& Cadmium
3 Boron & Aluminium
1,2 Copper & Mercury
1,3 Gold
2,3 Iron, Cobalt & Nickel
2,4 Palladium,, Platinum, Tin & lead
Valence Elements
- 1 Fluorine, Chlorine, Bromine & iodine
- 2 Sulphur, Selenium & Tellurium

4. 1. Figuring out oxidation numbers
 Oxidation number for a neutral element
equals to zero
 Oxidation number for a simple ion
equals to its own electric charge
 Oxidation number for hydrogen is +1 ,
except in hydrides, in which it´s – 1
 Oxidation number for oxygen is – 2,
except in peroxides, in which it is – 1
 The sum of all the atom´s oxidation
numbers in a neutral substance equals to
zero
 The sum of all the atom´s oxidation
numbers in an ion equals to its own
charge

5. 2. Types of nomenclature
 Compositional nomenclature
 easiest system of nomenclature based on the
composition of the substance.
 Stoichiometric naming system use multiplicative
prefixes, such as di, tri, tetra, SO3 : sulphur trioxide
H2SO4: dihydrogen (tetraoxidosulphate
 Numbers of oxidation can also be used to specify the
substance FeCl3: iron (III) choride
 Additive nomenclature
 Central atom and ligands: SO3 : trioxidosulphur
H2SO4: dihydroxidodioxidosulphur
 Substitutive
 Parent hydrides which are modified by substituting
atoms of hydrogen by different groups of atoms
 CH4: methane CH3Cl: chloromethane
 PH3: phosphane PCl3: trichlorophosphane

6. 3. Ions
 Atom or molecule which has electrical charge
 A cation is a positively charged ion. An anion is a
negatively charged ion
 Monovalent cations: same name:
e.g.: Na+: sodium ion; Al3+: aluminium ion
 Multivalent cations: labeled with a Roman numeral or just
a number in parenthesis following the cation´s name
e. g. Cu*: copper (I) ion; Cu2+: copper (+ 2) ion.
 Some cations have a common name: ammonium, NH4
+.
 Monoatomic anions adding the sufix –ide
Cl (chlorine) Cl- : chloride; O: oxygen O2- : oxide
 Polyatomic anions: adding the suffixes –ite and –ate to
the root of the element

7. 4. Binary substances: formula writing
 Substances which consist of two
elements, on positive and the
other negative
 Positive element precedes
negative.
 Stoichiometry is the ratio of
both elements in the formula,
which is shown with subscripts.
 If both charges are the same, the ratio is
1:1: no subscripts are needed
 If oxidation numbers are different, use
the “criss-cross” method.
 Reduce subscripts when possible

8. 4. Binary substances: naming systems
 Name of the cation followed by the name of
the anion
Metal + Nonmetal + IDE
 Stoichiometric Compositional name:
multiplicative prefixes are used to show the
numeber of atmos of each element in the
formula. These prefixes are:
mono- (1:1), di-, tri-, tetra-,
penta-, hexa- & hepta- .
 Oxidation numbers: oxidation numbers are
shown after the name of the cation to
determine the number of anion atoms
 IUPAC recommends the use of
stoichichiometric nomenclature
 Traditional nomenclature is not accepted

9. 4.1. Hydrides
 Consist of metal &
hydrogen
 Oxidation number for
hydrogen: -1
 General formula: MHx.
 Naming system: cation
+ hydride
 Multivalent cations:
stoichiometric or oxidation
numbers

10. 4.1. Parent hydrides
Substitutive nomenclature
IUPAC before 2005
 NH3: ammonia
 PH3: phosphine
 AsH3: arsine
 SbH3: estibine
H2O:
water
(oxidane)
NH3:
ammonia
or azane
CH4:
methane
BH3:
borane
PH3:
phospha
ne
SiH4:
silane
AsH3:
arsane
SbH3:
stibane

11. 4.2. Oxides
 Consist of an element &
oxygen
 Oxidation number for
oxygen: - 2
 General formula X2Ox,
 XOx/2 x even number
 Naming: element + oxide
 Multivalent cations:
stoichiometric or
oxidation numbers

12. 4.3. Peroxides
 Consist of peroxide ion O2
2-,
which has valence - 2, and
alcaline or earthalcaline
 General formula M2(O2)x.
 Naming:
 Element + peroxide
 Stoichiometric: Element +
dioxide

13. 4.4. Binary salts: halides
 Oxidation number halogen: - 1
 Consist of an element an
halogen
 General formula : MXm.
 Naming element + root + ide
 Multivalent cations:
stoichiometric or oxidation
numbers
 Binary acids: hydrogen + halogen
 Traditional Hydro + root + ic
acid
Formula Stoichiometric Tradicional
HF Hydrogen
fluoride
Hydrofluoric
acid
HCl Hydrogen
chloride
Hydrochloric
acid
HBr Hydrogen
bromide
Hydrobromic
acid
HI Hydrogen
iodide
Hydroiodic
acid

14. 4.5. Binary salts: chalcogens
Formula Stoichiometric Traditional
H2S Hydrogen
sulphide
Hydrosulphur
ic acid
H2Se Hydrogen
selenide
Hydroselenic
acid
H2Te Hydrogen
telluride
Hydrotelluric
acid
 Chalchogens : Sulphur , selenium,
tellurium
 Oxidation number chalcogens: - 2
 General formula : X2Sx,
 XSx/2 x even number
 Naming element + root + ide
 Multivalent cations: stoichiometric
or oxidation numbers
 Binary acids: hydrogen + chalcogen
 Traditional Hydro + root + ic acid

15. 5. Hidroxides
 Substances whic consist of
element and hydroxide group
 Valence for hydroxide: - 1
 General formula M(OH)x.
 Naming: element + hydroxide
 Multivalent cations:
stoichiometric or oxidation
numbers

16. 6. Oxoacids
 Substances which consist of nonmetal,
oxygen and hydrogen
 General formula HaXbOc
 Positive ion precedes negative one
 Types of nomenclature
 Hydrogen nomenclature:
Compositional nomenclature
Hydrogen( Prefix+oxido+element+ate)
 Traditional Set of prefixes and suffixes
combined to the name of the element
hypo-ous, -ous, -ic y per-ic), related to the
oxidation number of the central atom

17. 6. Oxoacids
Prefijos Nº OXID Cl / Br / I N P / As / Sb B
HYPO-OUS I HClO, HBrO … - - -
- OUS III HClO2, HBrO2 . HNO2 H3PO3 -ous
H4P2O5 di - ous
HBO2 meta- ic
H3BO3 - ic
- IC V HClO3, HBrO3.. HNO3 HPO3 meta- ic
H3PO4 -ic
H4P2O7 di - ic
-
PER-IC VII HClO4, HBrO4.. - - -
Phosphorous, arsenic, antimony, boron: Three different acids
Meta
Orto : one molecule of water added
HPO3 + H2O → H3PO4
Di : dimer. Condensation of 2 molecules of acid
 2 H3PO4 → H4P2O7 + H2O

18. 6. Oxoacids
Prefijos Nº S / Se / Te Cr C Si Mn
HYPO-
OUS
II H2SO2, H2SeO2.. - - - -
- OUS IV H2SO3, H2SeO3.. - H2CO3
- ic
H2SiO3 meta
H4SiO4
-
- IC VI H2SO4, H2SeO4..
H2S2O7 di - ic
H2CrO4
H2Cr2O7 di - ic
- - H2MnO4
PER - IC VII - - - - HMnO4
 Sulphur & chromium: dimers
 Silicon: meta

19. 7. Oxosalts
 Traditional: cation + anion
 Multivalent cations:
cation (oxidation number) + anion
 Stoichiometric:
 Metal Prefix + oxido + element+ate)

20. 7. Oxosalts
 Salts: hydrogen atoms are substituted by metals
 Acid valence: number of atoms of hydrogen lost by the acid
 Anion: OUS ITE
IC ATE

21. 8. Acid salts
 Acid doesn´t lose all the atoms of
hydrogen
 Traditional: cation +hydrogen
anion
 Stoichiometric:
 Metal hydrogenPrefix + oxido +
element+ate)
 Prefix Bi: forbidden