MM O O LECULES LECULES ANDAND IONSIONS
INORGANICINORGANIC CHEMISTRYCHEMISTRY NOMENCLATURENOMENCLATURE(T(T P P 1) 1) Compounds
•Compound is a substance that contains atoms of more than one element. Additionally, the proportion of these elements in the compound is well-defined and constant. ¾ Organic compounds: usually contains carbon atoms bonded to hydrogen atoms. They can also have atoms of other elements (N, O, S, F, Cl, etc). The carbides, the carbonates, the cyanides and the carbon oxides are not organic compounds.
¾ Inorganic compounds: all the remainder. ¾ Molecular compounds: constituted by molecules. They are mainly formed between non-metallic elements. ¾ Ionic compounds: constituted by ions. They are mainly formed between metallic elements and non-metallic elements. CHEMICAL FORMULAS
• Molecular formula indicates the elementary composition of a molecular specie. Ethane: C2H6
¾ Empirical formula only indicates the proportion of the proportion of the elements, without specifying the exact number of atoms of each element in the molecule. Ethane: CH3 ¾Structural formula indicates which atoms are directly bonded. Ethane:
¾Molecular model indicates specifically the structure and the
geometry of the molecule. Ethane:
A molecular formula shows the exact number of atoms of each element in the smallest unit of a substance.
An empirical formula shows the simplest whole-number ratio of the atoms in a substance
molecular empirical
H2O H2O
C6H12O6 CH2O
O3 O
N2H4 NH2 Predict the type of compound by the respective chemical formula
•P2O5 • Molecular inorganic compound •SrO • Ionic inorganic compound (Sr2+ and O2-)
3+ - •FeCl3 • Ionic inorganic compound (Fe and Cl )
•C2H6O • Molecular organic compound
•CO2 • Molecular inorganic compound
2+ 2- •CaCO3 • Ionic inorganic compound (Ca and CO3 ) INORGANIC CHEMISTRY NOMENCLATURE
Prefixes Prefix Meaning mono 1 di 2 tri 3 tetra 4 penta 5 hexa 6 hepta 7 octa 8 nona 9 deca 10 INORGANIC CHEMISTRY NOMENCLATURE Monoatomic cations The name of a monoatomic cation is equal to the name of the correspondent elements, with its oxidation number appended in parentheses. If the element only presents an oxidation number, this is usually omitted.
Examples:
Ni2+: nickel (II); Na+: sodium;
Ca2+: calcium; Ti4+: titanium (IV).
Li+: Lithium; Cr3+: chromium (III).
Al3+: aluminum; Mo6+: molybdenum (VI). INORGANIC CHEMISTRY NOMENCLATURE Polyatomic cations A polyatomic cation, obtained from the addition of H+ to a base, is named by adding the suffix “onium” to the first part of the name of initial specie.
Examples: + + PH3 + H → PH4 Phosphine Cation phosphonium
+ + NH3 + H → NH4 Amine Cation ammonium INORGANIC CHEMISTRY NOMENCLATURE Monoatomic anions A monoatomic anion is named by adding the suffix “ide” to the first part of the name of the respective element.
Examples: Group 1 Group 14 Group 15 Group 16 Group 17 H-: hydride C4-: carbide N3-: nitride O2-: oxide F-: fluoride Si4-: silicide P3-: phosphide S2-: sulfide Cl-: chloride As3-: arsenide Se2-: selenide Br-: bromide Sb3-: antimonide Te2-: telluride I-: iodide Bi3-: bismuthide INORGANIC CHEMISTRY NOMENCLATURE Homopolyatomic anions A homopolyatomic anion, constituted by atoms of the same element, is named by adding the suffix “ide” to the first part of the name of the respective element. Additionally, the numerical prefixes are also used for indicating the number of the atoms by anion. Examples:
2- S2 : anion disulphide.
- I3 : anion triiodide. INORGANIC CHEMISTRY NOMENCLATURE Polyatomic anions with non-systematic names
Examples:
- N3 : anion azide.
NH2-: anion imide.
- NH2 : anion amide.
CN-: anion cyanide. INORGANIC CHEMISTRY NOMENCLATURE Oxyanions
An oxyanion is a polyatomic ion containing oxygen, but structured around a central atom of other element.
The traditional nomenclature of oxyanions is based in the suffixes “ate” and “ite”.
If the central atom only presents an oxidation number, the suffix “ate” should be used.
If the central atom can present two oxidation numbers, the suffix “ate” should be used for the oxyanion for the oxyanion presenting the largest oxidation number and the suffix “ite” should be used for the oxyanion with the smallest oxidation number INORGANIC CHEMISTRY NOMENCLATURE Oxyanions
If the central atom can present more than two oxidation numbers, the prefix “per” when combined with the suffix “ate” should be used for the oxyanion with the largest oxidation number and the prefix “hypo” when combined with the suffix “ite” should be used for the oxyanion with the smallest oxidation number. For the oxyanions with intermediate oxidation numbers, the suffixes “ate” and “ite” should be used without any prefixes. INORGANIC CHEMISTRY NOMENCLATURE Oxyanions
Examples: 2- 3- CO3 : anion carbonate; BO3 : anion borate. 2- - CrO4 : anion chromate; OCN : anion cyanate. 3- 3- PO4 : anion phosphate, PO3 : anion phosphite. 2- 2- SO4 : anion sulfate; SO3 : anion sulfite. - - NO3 : anion nitrate, NO2 : anion nitrite.
- - ClO : anion hypochlorite; ClO2 : anion chlorite; - - ClO3 : anion chlorate; ClO4 : anion perchlorate.
- - BrO : anion hypobromite; BrO2 : anion bromite; - - BrO3 : anion bromate; BrO4 : anion perbromate. - - IO : anion hypoiodite; IO2 : anion iodite; - - IO3 : anion iodate; IO4 : anion periodate. INORGANIC CHEMISTRY NOMENCLATURE
Special prefixes
Prefix Meaning hydrogen addition of an acid hydrogen peroxo substitution of a group (-O-) by a group (-O-O-) thio substitution of a group (-O-) by a group (-S-)
Examples: 2- - HPO4 : anion hydrogen phosphate; H2PO4 : anion dihydrogen phosphate; SCN-: anion thiocyanate. INORGANIC CHEMISTRY NOMENCLATURE Polyatomic anions derived directly from oxygen The polyatomic anion, derived directly from oxygen, have non- systematic names finished by the suffix “ide”. Examples:
HO-: anion hydroxide.
2- O2 : anion peroxide.
- O2 : anion hyperoxide (or superoxide).
- O3 : anion ozonide. INORGANIC CHEMISTRY NOMENCLATURE Ionic compounds An ionic compound is named with the cation name first, followed by the name of the anion; the word ion is omitted in each case. Examples:
CaCl2: Calcium chloride; Fe2O3: iron (III) oxide; LiH: lithium hydride.
CaSO4: calcium sulfate; NaClO: sodium hypochlorite.
MgO: magnesium oxide; Ba(HSO3)2: barium hydrogen sulfite.
Bi(BrO2)3: bismuth (III) bromite; NiF2: nickel (II) fluoride.
NH4NO3: ammonium nitrate; Ca(OH)2; calcium hydroxide.
KNO2: potassium nitrite; Ba(ClO4)2: barium perchlorate. INORGANIC CHEMISTRY NOMENCLATURE Hydrated ionic compounds The name of hydrated ionic compound is formed by connecting the names of the components (ionic compound and water) by an ‘em’ dash; the proportions of the components are indicated after the names by a stoichiometric descriptor consisting in Arabic numerals separated by a slash. Examples:
FeSO4.7H2O: iron (II) sulfate – water (1/7)
Na2HPO4.4H2O: sodium hydrogen phosphate – water (1/4)
CuSO4.5H2O – copper (II) sulfate – water (1/5)
CoI2.6H2O – cobalt (II) iodide – water (1/6)
SnCl2.7H2O – tin (II) chloride – water (1/7) INORGANIC CHEMISTRY NOMENCLATURE Hydrated ionic compounds (alternative nomenclature) The name of hydrated ionic compound is formed by connecting the names of the ionic compound and the word “hydrate”. The Greek numeric prefixes, previously presented, are attached to the word "hydrate" to indicate the number of water molecules per formula unit for the ionic compound. Examples:
FeSO4.7H2O: iron (II) sulfate heptahydrate
Na2HPO4.4H2O: sodium hydrogen phosphate tetrahydrate
CuSO4.5H2O – copper (II) sulfate pentahydrate
CoI2.6H2O – cobalt (II) iodide hexahydrate
SnCl2.7H2O – tin (II) chloride heptahydrate INORGANIC CHEMISTRY NOMENCLATURE Binary molecular compounds
A binary molecular compound is named in a similar way of a ionic compound. A compound of this type is named with the cation name associated with the most electropositive element first, followed by the name of the anion associated with the most electronegative element. The Greek numeric prefixes, previously presented, are used to indicate the number of each atom in a molecule. The prefix “mono” is usually omitted for the most electropositive element, but not for the most electronegative one. INORGANIC CHEMISTRY NOMENCLATURE Binary molecular compounds
Examples:
CO2: carbon dioxide; BF3: boron trifluoride;
HI: hydrogen iodide; NF3: nitrogen trifluoride.
SO2: sulfur dioxide; N2Cl4: dinitrogen tetrachloride.
N2O5: dinitrogen pentoxide; CO: carbon monoxide.
NO2: nitrogen dioxide; N2O: dinitrogen oxide. INORGANIC CHEMISTRY NOMENCLATURE
Binary molecular compounds with non-systematic names
Examples:
H2O: water; NH3: ammonia; N2H4: hydrazine; PH3: phosphine.
AsH3: arsine: SbH3: Stibine; CH4: methane; SiH4: silane.
BH3: borane. INORGANIC CHEMISTRY NOMENCLATURE Acids The name of the inorganic acids are derived from the name of the associated anions, by replacing the suffix of anion by an appropriate suffix and by adding the word “acid”. For the anions associated with suffix “ide”, the prefix “hydro” should be added to the name of the correspondent acid
Suffix of the anion Prefix of the acid Suffix of the acid ide hydro ic ate _____ ic ite _____ ous INORGANIC CHEMISTRY NOMENCLATURE Acids Anion Acid F-: fluoride HF: hydrofluoric acid Cl-: chloride HCl: hydrochloric acid Br-: bromide HBr: hydrobromic acid I-: iodide HI: hydroiodic acid CN-: cyanide HCN: hydrocyanic acid
- NO3 : nitrate HNO3: nitric acid 2- SO4 : sulfate H2SO4: sulfuric acid 2- CO3 : carbonate H2CO3: carbonic acid 3- PO4 : phosphate H3PO4: phosphoric acid - ClO4 : perchlorate HClO4: perchloric acid - ClO3 : chlorate HClO3: chloric acid INORGANIC CHEMISTRY NOMENCLATURE Acids
Anion Acid - NO2 : nitrite HNO2: nitrous acid 2- SO3 : sulfite H2SO3: sulfurous acid 3- PO3 ; phosphite H3PO3: phosphorous acid ClO-: hypochlorite HClO: hypochlorous acid - ClO2 : chlorite HClO2: chlorous acid 1. Name the inorganic species associated with the following chemical formulas: −; 2+; − − − a) HSO4 b) Hg2 c) H2PO4 ; d) HCO3 ; e) NO2 f ) HClO4; g) H2S; h) KCl
2. Write the chemical formulas of the following inorganic compounds: a) Magnesium oxide ; b) calcium phosphate; c) aluminum sulfate; d) barium nitrate; e) sodium nitrite; f) calcium hydroxide; g) iron (III) oxide; h) lead sulfite; i) dinitrogen tetroxide; j) copper sulfate pentahydrate; l) Sodium hydrogen carbonate; m) phosphorus pentachloride.