Inorganic Compound Nomenclature Example

The nomenclature of inorganic compounds: Inorganic compounds are combinations of chemical elements, which have as a product molecules in which they are combine most of the chemical elements, but they do not have as the basis of their main structure the atoms of carbon. This does not mean that there are no inorganic molecules with carbon, but that these do not have the characteristics of organic molecules.

Throughout history, many substances have been given various names, some of which have endured to this day. This is the case, for example, with the substance known as salfumán, salt spirit, sea acid or muriatic acid. Substance that has been known since ancient times, has had various uses and various names.

Faced with this diversity of the names of chemical compounds and molecules, and the need to have unified rules useful to all scientists, academics, students and industrialists, in 1919 the IUPAC (International Union of Pure and Applied Chemistry: International Union of Pure and Applied Chemistry), which is the body in charge of establishing the names and symbols of chemical elements, as well as to standardize the names of molecules and compounds chemicals.

The IUPAC has admitted two systems for naming inorganic chemical compounds, which together with the traditional system are used today.

Traditional nomenclature:

It is the oldest system, currently it is used mainly in commerce and some traditional industries. Use some suffixes to indicate the difference between substances made up of the same elements in different combinations, using the suffix –oso for the lower valences, and –ico for the more high.

• Example: FeO: Ferrous oxide; Faith₂OR₃: Ferric oxide; Faith₃OR₄: Ferrous-ferric oxide.

Stock Nomenclature:

Widely used throughout much of the 20th century, it uses Roman numerals to identify compounds of similar structures in which some of the elements react with different valences.

• Example: FeO: Iron (II) oxide; Faith₂OR₃: Iron (III) oxide; Faith₃OR₄: Iron (II, III) oxide.

Stoichiometric nomenclature:

The stoichiometric nomenclature is the most recent and the one that is used mainly among researchers and academics, since has a simpler structure by using numerical prefixes that indicate the number of atoms or ions of each substance in the molecule.

• Example: FeO: Iron oxide; Faith₂OR₃: di iron trioxide; Faith₃OR₄: Tri-iron tetraoxide

Writing chemical formulas.

As part of the nomenclature, the writing of the chemical formula of a compound must be written following a certain order of the elements and its reading also follows a rule.

The most electro-positive elements are written first, and last the elements or radicals that act with electronegative valence.

Example: In the case of hydrogen, when it combines with a nonmetal to form an acid it has a positive valence, while the nonmetal has a negative valence. So first the symbol for Hydrogen will be written and then the symbol for chlorine: H⁺ + Cl^– = HCl.

In the case of a hydride, hydrogen acts with a negative valence and the metal has a positive valence, so the metallic element will be written first and then Hydrogen: Na⁺ + H^– = NaH

In the case of a radical, such as the Oxyhydrile radical (–OH), it always acts with negative valence, so it will be written at the end of the formula: Na⁺ + OH^– = NaOH

The way of reading is done from right to left, that is, the element or radical electronegative gives the type of compound in question, and the positive radical the component that affects. In the case of acids, the name is given according to its structure, so according to this rule it is named after the element electro negative or acid, will be correct forms, although the preferred is to name it as acid, with the ending –Hydric. In the above examples, the compounds will have the following names:

HCl = Hydrogen Chloride and Hydrochloric Acid (this should be used preferably).
NaH = Sodium Hydride.
NaOH = Sodium Hydroxide.
In the case of a salt.
FeCl₃ = Ferric chloride (traditional), Iron II chloride (Stock), iron trichloride (stoichiometric).

10 Examples of nomenclatures of inorganic compounds:

1. H₂SW₄ (2 hydrogen atoms + sulfate ion [SO₄])
Traditional nomenclature: Vitriol oil, Vitriol spirit, Sulfuric acid.
Stock Nomenclature: Sulfuric acid.
Stoichiometric Nomenclature: Sulfuric diacid.

2. Cu₂SW₄. (2 copper atoms + sulfate ion).
Traditional nomenclature: vitriol, cuprous sulfate.
Stock Nomenclature: Copper sulfate I.
Stoichiometric Nomenclature: Dicobre sulfate.

3. Cu₂SW₄. (2 copper atoms + sulfate ion).
Traditional nomenclature: vitriol, cuprous sulfate.
Stock Nomenclature: Copper sulfate I.
Stoichiometric Nomenclature: Dicobre sulfate.

4. CS₂. (carbon atom + 2 sulfur atoms).
Traditional nomenclature: carbon sulfide.
Stock nomenclature: carbon sulfide.
Stoichiometric Nomenclature: carbon disulfide.

5. NaOH. (sodium atom + hydroxyl ion).
Traditional nomenclature: Caustic soda, sodium hydroxide.
Stock nomenclature: sodium hydroxide.
Stoichiometric Nomenclature: sodium hydroxide.

6. Ba (OH)₂. (barium atom + 2 hydroxyl ions).
Traditional nomenclature: barium hydroxide.
Stock nomenclature: barium hydroxide.
Stoichiometric Nomenclature: barium dihydroxide.

7. CuOH. (copper atom + hydroxyl ion).
Traditional nomenclature: Cuprous hydroxide.
Stock nomenclature: copper hydroxide I.
Stoichiometric Nomenclature: copper hydroxide.

8. Cu (OH)₂. (copper atom + 2 hydroxyl ions).
Traditional nomenclature: cupric hydroxide.
Stock nomenclature: copper hydroxide II.
Stoichiometric Nomenclature: copper dihydroxide.

9. AuOH. (gold atom + hydroxyl ion).
Traditional nomenclature: Aurous hydroxide.
Stock nomenclature: gold hydroxide I.
Stoichiometric Nomenclature: gold hydroxide.

10. Au (OH)₃. (barium atom + 3 hydroxyl ions).
Traditional nomenclature: auric hydroxide.
Stock nomenclature: gold hydroxide III.
Stoichiometric Nomenclature: barium trihydroxide.