BINARY MOLECULAR COVALENT COMPOUND

- Compound composed of two different non-metallic elements.

1. The more electronegative non-1. The more electronegative non-metallic element is written or metallic element is written or named last. This is usually the named last. This is usually the element present on the right side element present on the right side of the periodic table.of the periodic table.

STEPS IN NAMING BINARY STEPS IN NAMING BINARY MOLECULAR COVALENT MOLECULAR COVALENT

COMPOUNDCOMPOUND

2. Greek prefixes are used to identify the number 2. Greek prefixes are used to identify the number of atoms per element present. If the first of atoms per element present. If the first element consists of only one atom, the element consists of only one atom, the numerical prefix mono- is usually omitted.numerical prefix mono- is usually omitted.

11 mono-mono- 66 hexa-hexa-

22 di-di- 77 hepta-hepta-

33 tri-tri- 88 octa-octa-

44 tetra-tetra- 99 nona-nona-

55 penta-penta- 1010 deca-deca-

GREEK NUMERICAL PREFIXES

3. For the second element, the 3. For the second element, the stem name is retained and the stem name is retained and the suffix suffix –ide–ide is added to the it. is added to the it.

S O+6 -2

2 6S O

3

Sulfur trioxide

COCO22Carbon Carbon didioxoxideide

CClCCl44Carbon Carbon tetratetrachlorchlorideide

NN22OO DiDinitrogen nitrogen monmonoxoxideide

NN22OO44DiDinitrogen nitrogen tetrtetroxoxideide

PP22OO55DiDiphosphorus phosphorus

pentpentoxoxideide

EXCEPTIONS TO THE EXCEPTIONS TO THE RULERULE

HH22O -O - water water

NHNH3 3 -- ammoniaammonia

PHPH33 - - phosphinephosphine

CHCH44 - - methanemethane

- - contains polyatomic (more than contains polyatomic (more than one type of atom) ionsone type of atom) ions

- Naming follows the same step as - Naming follows the same step as binary ionic compounds, except binary ionic compounds, except that the name of the that the name of the metalmetal (using (using Roman numeral if necessary) is Roman numeral if necessary) is named or written first followed by named or written first followed by the name of the polyatomic ionthe name of the polyatomic ion

NAMES AND CHARGES OF SOME COMMON POLYATOMIC IONS

CHARGES

CHARGES

CaCaCOCO33calcium calcium carbonatecarbonate

KKNONO33potassiumpotassium nitrate nitrate

CuCu(OH)(OH)22copper (II)copper (II) hydroxidehydroxide

CuCu(OH)(OH)33copper (III)copper (III) hydroxidehydroxide

HgHgNONO33mercury (I)mercury (I) nitratenitrate

(NH(NH44))22SOSO

44

ammonium sulfateammonium sulfate

Non-metallic elementsNon-metallic elements combined with combined with oxygenoxygen to form to form non-metallic oxidenon-metallic oxide. The . The non-non-metallic oxidemetallic oxide reacts with reacts with

waterwater to form an acid. to form an acid.

NM NM + + OO22 = = NMONMO

NMONMO + + HH22OO ACIDACID

TWO TYPES OF ACIDSTWO TYPES OF ACIDSBINARY ACIDSBINARY ACIDS – compounds of – compounds of

hydrogen plus non-metal. hydrogen plus non-metal.

1.1. Add Add hydro-hydro- to the name of the NM. to the name of the NM.

2.2. Remove Remove –ide–ide and replace with and replace with –ic –ic acidacid..

Ex. Ex. HFHF – hydrogen fluor – hydrogen fluorideide (binary (binary compound)compound)

HydroHydrofluorfluoric acidic acid

HClHCl – hydrogen chlor – hydrogen chlorideide

HydroHydrochlorchloric acidic acid

OXYACID OXYACID – contains – contains hydrogen, oxygen and hydrogen, oxygen and another element.another element.

1. Polyatomic ion ends in 1. Polyatomic ion ends in –ate–ate, , replace replace –ate–ate with with –ic–ic acidacid..Ex. Ex. HH22SOSO44 – hydrogen sulf– hydrogen sulfateate

sulfursulfuricic acidacid2. Polyatomic ion ends in 2. Polyatomic ion ends in –ite–ite, ,

replace replace –ite–ite with with –ous–ous acidacid..Ex. Ex. HH22SOSO33 – hydrogen sulf – hydrogen sulfiteite

sulfursulfurousous acidacid

Metallic elementsMetallic elements combined combined with with oxygenoxygen to form to form metallic metallic

oxideoxide. The . The metallic oxidemetallic oxide reacts with reacts with waterwater to form a to form a

basebase..

MM + + OO22 = = MOMO

MOMO + + HH22OO BASEBASE

BASE – BASE – identified by the identified by the presence of the presence of the hydroxidehydroxide (–(–

OHOH) group) group

Write the name of the metal Write the name of the metal followed by the word followed by the word hydroxidehydroxide..

Ex. NaEx. NaOHOH – sodium – sodium hydroxidehydroxide

Al(Al(OHOH))33 – aluminum – aluminum hydroxidehydroxide

Fe(Fe(OHOH))22 – iron (II) – iron (II) hydroxidehydroxide

Fe(Fe(OHOH))33 – iron (III) – iron (III) hydroxidehydroxide