BINARY MOLECULAR COVALENT COMPOUND - Compound composed of two different non-metallic elements.

STEPS IN NAMING BINARY MOLECULAR COVALENT COMPOUND 1. The more electronegative non-metallic element is written or named last. This is usually the element present on the right side of the periodic table. O + S = SO or OS?

GREEK NUMERICAL PREFIXES 2. Greek prefixes are used to identify the number of atoms per element present. If the first element consists of only one atom, the numerical prefix mono- is usually omitted. GREEK NUMERICAL PREFIXES 1 mono- 6 hexa- 2 di- 7 hepta- 3 tri- 8 octa- 4 tetra- 9 nona- 5 penta- 10 deca-

3. For the second element, the stem name is retained and the suffix –ide is added to the it. O + S = SO? +6 -2 S O S O 3 2 6 Sulfur trioxide

Diphosphorus pentoxide CO2 Carbon dioxide CCl4 Carbon tetrachloride N2O Dinitrogen monoxide N2O4 Dinitrogen tetroxide P2O5 Diphosphorus pentoxide

EXCEPTIONS TO THE RULE H2O - water NH3 - ammonia PH3 - phosphine CH4 - methane

TERNARY IONIC COMPOUNDS - contains polyatomic (more than one type of atom) ions - Naming follows the same step as binary ionic compounds, except that the name of the metal (using Roman numeral if necessary) is named or written first followed by the name of the polyatomic ion

NAMES AND CHARGES OF SOME COMMON POLYATOMIC IONS

copper (III) hydroxide CaCO3 calcium carbonate KNO3 potassium nitrate Cu(OH)2 copper (II) hydroxide Cu(OH)3 copper (III) hydroxide HgNO3 mercury (I) nitrate (NH4)2SO4 ammonium sulfate

NAMING ACIDS AND BASES

Non-metallic elements combined with oxygen to form non-metallic oxide Non-metallic elements combined with oxygen to form non-metallic oxide. The non-metallic oxide reacts with water to form an acid. NM + O2 = NMO NMO + H2O  ACID

TWO TYPES OF ACIDS BINARY ACIDS – compounds of hydrogen plus non-metal. Add hydro- to the name of the NM. Remove –ide and replace with –ic acid. Ex. HF – hydrogen fluoride (binary compound) Hydrofluoric acid HCl – hydrogen chloride Hydrochloric acid

OXYACID – contains hydrogen, oxygen and another element. 1. Polyatomic ion ends in –ate, replace –ate with –ic acid. Ex. H2SO4 – hydrogen sulfate sulfuric acid 2. Polyatomic ion ends in –ite, replace –ite with –ous acid. Ex. H2SO3 – hydrogen sulfite sulfurous acid

Metallic elements combined with oxygen to form metallic oxide Metallic elements combined with oxygen to form metallic oxide. The metallic oxide reacts with water to form a base. M + O2 = MO MO + H2O  BASE

BASE – identified by the presence of the hydroxide (–OH) group Write the name of the metal followed by the word hydroxide. Ex. NaOH – sodium hydroxide Al(OH)3 – aluminum hydroxide Fe(OH)2 – iron (II) hydroxide Fe(OH)3 – iron (III) hydroxide