Chapter 6 - Nomenclature

Chemical Names&

Formulas

Introduction to Chemical Bonding

Two types of Bonding Ionic Bonding - transfer of electrons

Covalent Bonding - sharing of electrons

Bonding takes place at the highest energy level, s and p sublevels.

If there are less than half the electrons between the s and p sublevels, the atom will lose the electrons.

If there are half or more electrons between the s and p sublevels, the atom will gain electrons.

Know the trends on the periodic table for how many electrons will be gained or lost.

Ionic BondingBecause there is a transfer of

electrons, elements will lose or gain electrons.

If an element loses or gains electrons, it will then become a charged particle - ion. Positive ion - cation Negative ion - anion

CationsSubstance that has lost electrons. The charge is equal to the number of

electrons that are transferred.Ca2+ - calcium that has transferred

two electrons to another substance (anion).

Mg2+ - magnesium that has transferred two electrons to another substance (anion).

AnionSubstance that has gained electrons. The charge is equal to the number of

electrons that are transferred.F1- - fluorine that has accepted one

electron from another substance (cation).

O2- - oxygen that has accepted two electrons from another substance (cation).

Ionic BondingIonic bonding is the accepting

or donating of electrons.Metals are donors.Nonmetals are acceptors.Hence, ionic bonding will occur

between metals and nonmetals.

Oxidation NumbersPossible charges on an

element.Any single element, by itself,

has a charge of zero.An element takes on a charge

when put with other elements.

Basic Rules of Oxidation NumbersGroup 1 elements are always

1+.Group 2 elements are always

2+.Group 17 elements will be 1-.Group 16 elements will be 2-.Group 15 elements will be 3-.

Writing Formulas from Ions

The total overall charge of a compound is zero.

Use subscripts to balance the charge to zero.

Ca2+and S2-

CaS

Na+ and Cl- NaCl

Ba2+and N3-

Ba3N2

Writing Ions from Compounds

Go with what you know.

MgCl2 Mg2+ and Cl-

CuBr2

Cu2+ and Br-

FeCl3 Fe3+ and Cl-

Polyatomic IonsMany atomed charged particle that

acts as a single unit.Polyatomic ions have specific names.

Use the names.Common polyatomic ions include:

Nitrate ____________ Sulfate ____________ Phosphate ____________ Carbonate ____________ Hydroxide ____________ Chlorate ____________

Ba2+ and SO42-

BaSO4

Na+ and ClO3-

NaClO3

Fe2+ and CO32-

FeCO3

KNO3

K+ and NO3-

CoSO4

Co2+ and SO42-

LiClO3

Li+ and ClO3-

More than one of the Polyatomic Ion Needed to Balance the Charge

If more than one of the polyatomic ions is needed to balance the charge, you must use parentheses () around the ion.

Ba(NO3)2

Ba2+ and NO3-

Mg2+ and ClO3-

Mg(ClO3)2

Fe3+ and SO42-

Fe2(SO4)3

Co3+and NO3-

Co(NO3)2

Naming Ionic Compounds

Binary Ionic Compounds - Types 1 & 2 A compound that contains a

positive ion (cation) and a negative ion (anion).

Bi- means two Positive ion is written first, negative

ion is written second in a chemical formula.

Type 1 - Binary Ionic Compound

The cation of a Type 1 has only one possible charge.

Name the first element (cation) as is.

Name the second element (anion) as is with an ending of “-ide”.

Example: CaCl2 Calcium chloride

More Examples:

NaBr - Sodium bromideMgO - Magnesium oxideKBr - Potassium

bromideBaS - Barium sulfide

Type 2 - Binary Ionic Compounds

The cation has multiple charges - copper can have a charge of 1+ or 2+.

Determine which charge is being used. Use the anion as the guide.

Name the element as is.Use a Roman numeral to indicate

the charge being used.

Name the anion as is, using an ending of “-ide” as with Type 1 compounds.

Example: CuCl2 Copper (II) chloride

MnO2 - Manganese (IV) oxide

NiO - Nickel (II) oxide

Naming Type 1 & 2 with Polyatomic Ions

Form compounds called ternary compounds - compound that contains atoms of three different elements.

Polyatomic Ion - many atomed charged particle acting as a single unit. poly - many atomic - atom ion - charged particle

Polyatomic Ions - few examples

NO31- - nitrateSO4

2- - sulfate

PO43- - phosphate

CO32- - carbonate

ClO31- - chlorate

OH1- - hydroxide

Type 1 & 2 Compounds with Polyatomic Ions

Name the cation using the rules for Type 1 or Type 2 compounds.

Name the polyatomic ion as is - use the name on the chart.

Examples: NaNO3 - sodium nitrate BaSO4 - barium sulfate

Name these:LiOH - lithium hydroxideMg(NO3)2 - magnesium nitrate

CrCl3 - chromium (III) chloride

Al2O3 - aluminum oxide

CoBr2 - cobalt (II) bromide

Fe2O3 - iron (III) oxide

Covalent BondingCovalent bonding involves the sharing of

electrons between substances.Molecule - smallest neutral unit of a

substance that still has the properties of the substance.

Molecular formula - shows the kinds of numbers of atoms present in a molecule of a compound.

Occurs between nonmetals and nonmetals.

Because these are molecules and are covalently bonded, ions are not formed - there is no transferring of electrons to form ions.

Prefixes are used in naming nonmetal-nonmetal compounds.

Prefixesmono - 1di- - 2tri- - 3tetra- - 4penta- - 5hexa- - 6hepta- - 7octa- - 8nona- - 9deca- - 10

Prefixes:Only used for nonmetal-

nonmetal compounds.Mono- is never used on the

first element.Second element always has

a prefix.

Naming Molecular CompoundsName the first element as is. If there

is more than one of the first element, you must use a prefix.

Name the second element with a prefix to indicate how many atoms there are and add the ending “-ide”.

Example: CO2 - carbon dioxide

Name these:N2O - dinitrogen monoxide

PCl3 - phosphorus trichloride

SF6 - sulfur hexafluoride

P4O6 - tetraphosphorus hexaoxide

SO2 - sulfur dioxide

NO3 - nitrogen trioxide

SO4 - sulfur tetraoxide

Naming AcidsWhen dissolved in water, certain

molecules produce hydrogen ions - H+.

These substances are called acids.An acid can be viewed as a molecule

with one or more H+ ions attached to an anion.

The rules for naming acids depend on whether the anion contains oxygen.

Naming AcidsIdentify the compound as being an

acid - the first element is hydrogen (two exceptions are H2O and H2O2)

Find the anion on the chart.Name the anion.Following across to the name of

the acid.Name the acid.

Naming Acids

If you move up the chart, you gain oxygen.

If you move down the chart, you lose an oxygen.

Start with what you know - usually the -ate group.

Examples:HCl

The chloride ion (anion) is a single element and ends in “-ide”.

It is at the bottom of the chart. Move across and the name of this acid is hydrochloric acid.

H3PO4

The anion is phosphate. Move across to the acids and the name of this acid is phosphoric acid.

H2SO4

The anion is sulfate. Move across to the acids and the name of this acid is sulfuric acid.

HClO2

Identified as an acid. The anion is ClO2

1-, which is one less oxygen than chlorate, ClO3

1-. Lose an oxygen, move down the chart.

Move down the chart and the name of the anion is chlorite.

Move across to the acid and the name of this acid is chlorous acid.

Name these:HNO3 - nitric acid

H2CO3 - carbonic acid

H2SO3 - sulfurous acid

HNO2 - nitrous acid

HC2H3O2 - acetic acid

HClO4 - perchloric acid