Generally, there are two types of inorganic compounds that have the right to be formed: ionic compounds and molecular compounds. Nomenclature is the procedure of specify name yellowcomic.comical link with different names so that they can be easily determined as different yellowcomic.comicals. Not natural compounds are compounds that execute not attend to the formation of carbohydrates, or just all various other compounds that carry out not fit right into the description of an necessary compound. Because that example, essential compounds include molecules through carbon ring and/or chains through hydrogen atoms (see photo below). Not natural compounds, the object of this section, are every various other molecule that does not include these distinctive carbon and also hydrogen structures.

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Compounds in between Metals and Nonmetals (Cation and Anion)

Compounds make of a metal and nonmetal are generally known as Ionic Compounds, wherein the compound name has an ending of –ide. Cations have actually positive charges while anions have an unfavorable charges. The net charge of any kind of ionic compound should be zero i m sorry also means it should be electrically neutral. Because that example, one Na+ is paired with one Cl-; one Ca2+ is paired v two Br-. There room two rule that need to be followed through:

The cation (metal) is always named first with that is name unmodified The anion (nonmetal) is created after the cation, modified to finish in –ide Table 1: Cations and Anions: +1 Charge+2 Charge-1 Charge-2 Charge-3 Charge-4 Charge
Group 1A elements Group 2A elements Group 7A elements Group 6A elements Group 5A elements Group 4A elements
Hydrogen: H+ Beryllium: Be2+ Hydride: H- Oxide: O2- Nitride: N3- Carbide: C4-
Lithium: Li+ Magnesium: Mg2+ Fluoride: F- Sulfide: S2- Phosphide: P3-
Soduim: Na+ Calcium: Ca2+ Chloride: Cl-
Potassium: K+ Strontium: Sr2+ Bromide: Br-
Rubidium: Rb+ Barium: Ba2+ Iodide: I-
Cesium: Cs+

Example 1

Na+ + Cl- = NaCl; Ca2+ + 2Br- = CaBr2

Sodium + Chlorine = salt Chloride; Calcium + Bromine = Calcium Bromide

The change metals may form more 보다 one ion, thus it is needed to be stated which specific ion we are talking about. This is suggested by assigning a Roman numeral after the metal. The Roman character denotes the charge and also the oxidation state of the shift metal ion. Because that example, iron can kind two usual ions, Fe2+ and also Fe3+. To differentiate the difference, Fe2+ would be called iron (II) and Fe3+ would certainly be called iron (III).

Table of change Metal and also Metal Cations: +1 Charge+2 Charge+3 Charge+4 Charge
Copper(I): Cu+ Copper(II): Cu2+ Aluminum: Al3+ Lead(IV): Pb4+
Silver: Ag+ Iron(II): Fe2+ Iron(III): Fe3+ Tin(IV): Sn4+
Cobalt(II): Co2+ Cobalt(III): Co3+
Tin(II): Sn2+
Lead(II): Pb2+
Nickel: Ni2+
Zinc: Zn2+

Example 2

Ions: Fe2++ 2Cl- Fe3++ 3Cl-
Compound: FeCl2 FeCl3
Nomenclature Iron (II) Chloride Iron (III) Chloride

However, several of the shift metals" charges have particular Latin names. Similar to the various other nomenclature rules, the ion the the change metal that has actually the lower charge has the Latin name finishing with -ous and also the one through the the greater charge has a Latin name ending with -ic. The most usual ones are presented in the table below:

Transition metal Ion v Roman NumeralLatin name
Copper (I): Cu+ Cuprous
Copper (II): Cu2+ Cupric
Iron (II): Fe2+ Ferrous
Iron (III): Fe3+ Ferric
Lead (II): Pb2+ Plumbous
Lead (IV): Pb4+ Plumbic
Mercury (I): Hg22+ Mercurous
Mercury (II): Hg2+ Mercuric
Tin (II): Sn2+ Stannous
Tin (IV): Sn4+ Stannic

Several exceptions use to the Roman numeral assignment: Aluminum, Zinc, and also Silver. Although castle belong to the change metal category, these metals do not have Roman numerals composed after their names because these steels only exist in one ion. Instead of making use of Roman numerals, the various ions can likewise be presented in level words. The metal is changed to finish in –ous or –ic.

-ic ending is offered for the higher oxidation state

Example 3

Compound Cu2O CuO FeCl2 FeCl3
Charge Charge of copper is +1 Charge that copper is +2 Charge of stole is +2 Charge of stole is +3
Nomenclature Cuprous Oxide Cupric Oxide Ferrous Chloride Ferric Chloride

However, this -ous/-ic mechanism is inadequate in some cases, therefore the roman numeral system is preferred. This device is used frequently in specify name acids, wherein H2SO4 is typically known together Sulfuric Acid, and H2SO3 is known as Sulfurous Acid.

Compounds between Nonmetals and also Nonmetals

Compounds the consist that a nonmetal external inspection to a nonmetal are commonly known as Molecular Compounds, wherein the element with the optimistic oxidation state is created first. In countless cases, nonmetals form more than one binary compound, therefore prefixes are used to distinguish them.

# that Atoms12345678910
Prefixes Mono- Di- Tri- Tetra- Penta- Hexa- Hepta- Octa- Nona- Deca-

Example 4

CO = carbon monoxide BCl3 = borontrichloride

CO2 = carbon dioxide N2O5 =dinitrogen pentoxide

The prefix mono- is not offered for the very first element. If over there is not a prefix before the first element, the is assumed the there is only one atom of that element.

Binary Acids

Although HF deserve to be named hydrogen fluoride, the is offered a different name for focus that the is one acid. An acid is a substance that dissociates right into hydrogen ion (H+) and anions in water. A quick means to determine acids is to watch if over there is an H (denoting hydrogen) in front of the molecular formula of the compound. To name acids, the prefix hydro- is placed in front of the nonmetal modification to end with –ic. The state of mountain is aqueous (aq) due to the fact that acids are discovered in water.

Some usual binary acids include:

HF (g) = hydrogen fluoride -> HF (aq) = hydrofluoric acid

HBr (g) = hydrogen bromide -> HBr (aq) = hydrobromic acid

HCl (g) = hydrogen chloride -> HCl (aq) = hydrochloric acid

H2S (g) = hydrogen sulfide -> H2S (aq) = hydrosulfuricacid

It is vital to encompass (aq) after ~ the acids since the same compounds have the right to be composed in gas phase v hydrogen named an initial followed by the anion finishing with –ide.

Example 5

hypo____ite ____ite ____ate per____ate

ClO- ClO2- ClO3- ClO4-

hypochlorite chlorite chlorate perchlorate


As shown by the arrow, relocating to the right, the following trends occur:

Increasing variety of oxygen atoms

Increasing oxidation state of the nonmetal

(Usage that this example can be viewed from the collection of link containing Cl and O)

This occurs since the variety of oxygen atom are raising from hypochlorite to perchlorate, however the as whole charge that the polyatomic ion is tho -1. To effectively specify how countless oxygen atoms room in the ion, prefixes and suffixes are again used.

Polyatomic Ions

In polyatomic ions, polyatomic (meaning 2 or much more atoms) room joined with each other by covalent bonds. Although there might be a aspect with positive charge prefer H+, that is not joined with one more element through an ionic bond. This occurs since if the atoms created an ionic bond, climate it would have already become a compound, for this reason not needing to obtain or loosened any electrons. Polyatomic anions are more common than polyatomic cations as shown in the graph below. Polyatomic anions have an adverse charges if polyatomic cations have actually positive charges. Come indicate various polyatomic ions consisted of of the exact same elements, the surname of the ion is modified according to the instance below:

Table: usual Polyatomic ions Name: Cation/Anion Formula
Ammonium ion NH4+
Hydronium ion


Acetate ion


Arsenate ion


Carbonate ion


Hypochlorite ion


Chlorite ion


Chlorate ion


Perchlorate ion


Chromate ion


Dichromate ion


Cyanide ion


Hydroxide ion


Nitrite ion


Nitrate ion


Oxalate ion


Permanganate ion


Phosphate ion


Sulfite ion


Sulfate ion


Thiocyanate ion

Thiosulfate ion


To incorporate the topic of acids and also polyatomic ions, there is nomenclature that aqueous acids. Together acids incorporate sulfuric mountain (H2SO4) or carbonic acid (H2CO3). To name them, follow these quick, simple rules:

If the ion end in -ate and also is added with one acid, the mountain name will have actually an -ic ending. Examples: nitrate ion (NO3-) + H+ (denoting formation of acid) = nitric acid (HNO3) If the ion ends in -ite and is included with an acid, then the mountain name will have actually an -ous ending. Example: nitite ion (NO2-) + H+ (denoting development of acid) = nitrous mountain (HNO2)


Pettrucci, Ralph H. General yellowcomic.comistry: ethics and contemporary Applications. 9th. Upper Saddle River: Pearson Prentice Hall, 2007 Nomenclature of inorganic yellowcomic.comistry, references 1990, Oxford:Blackwell clinical Publications. (1990) Bioyellowcomic.comical Nomenclature and Related Documents, London:Portland Press, 1992.


1. What is the exactly formula for Calcium Carbonate?

a. Ca+ + CO2-

b. CaCO2-

c. CaCO3

d. 2CaCO3

2. What is the correct name for FeO?

a. Stole oxide

b. Iron dioxide

c. Iron(III) oxide

d. Iron(II) oxide

3. What is the correct name for Al(NO3)3?

a. Aluminum nitrate

b. Aluminum(III) nitrate

c. Aluminum nitrite

d. Aluminum nitrogen trioxide

4. What is the correct formula the phosphorus trichloride?

a. P2Cl2

b. PCl3

c. PCl4

d. P4Cl2

5. What is the exactly formula that lithium perchlorate?

a. Li2ClO4

b. LiClO2

c. LiClO

d. No one of this

6. Write the correct surname for these compounds.

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a. BeC2O4:

b. NH4MnO4:

c. CoS2O3:

7. What is W(HSO4)5?

8. Just how do you create diphosphorus trioxide?

9. What is H3P?

10. By adding oxygens to the molecule in number 9, us now have H3PO4? What is the surname of this molecule?


1.C; Calcium + lead carbonate --> Ca2+ + CO32- --> CaCO3

2.D; FeO --> Fe + O2- --> stole must have actually a fee of +2 to do a neutral compound --> Fe2+ + O2- --> Iron(II) Oxide

3.A; Al(NO3)3 --> Al3+ + (NO3-)3 --> Aluminum nitrate

4.B; Phosphorus trichloride --> p + 3Cl --> PCl3

5.D, LiClO4; Lithium perchlorate --> Li+ + ClO4- --> LiClO4

6. a. Beryllium Oxalate; BeC2O4 --> Be2+ + C2O42- --> Beryllium Oxalate

b. Ammonium Permanganate; NH4MnO4 --> NH4+ + MnO4- --> Ammonium Permanganate

c. Cobalt (II) Thiosulfate; CoS2O3 --> Co + S2O32- --> Cobalt must have actually +2 fee to make a neutral compund --> Co2+ + S2O32- --> Cobalt(II) Thiosulfate

7. Tungsten (V) hydrogen sulfate

8. P2O3

9. Hydrophosphoric Acid

10. Phosphoric Acid

Contributors and also Attributions

Pui Yan Ho (UCD), Alex Moskaluk (UCD), Emily Nguyen (UCD)

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