Chapter 2b nomenclature Spring 2010 Stewardweb.gccaz.edu/~jaszi38221/2014/Fall/CHM 151...on the periodic table. Others cannot! Writing Ionic Formulas Any binary ionic formula has two

Chapter 2Chapter 2Chapter 2Chapter 2

Nomenclature

Chemical Nomenclature

Different types of compounds use different naming rules

– Covalent

– Ionic

– Polyatomic ions

– Acids

• Binary acids

• Oxo Acids

– Other molecules / with other naming rule which we will not

cover:

• Organic Molecules

• Complex Ions

Recognizing Bonding Patterns

�SO2

�NaBr

�H3PO4 (aq)

�P2O5

�BaSO4

�CoF3

�HI (aq)

�HCl (aq)

�CO2

�H2SO4 (aq)

�NiCl2�H2O

�KNO3

�CH3CH2CH3

Before you can name anything, you have to know what it is!!

Recognizing Bonding PatternsBefore you can name anything, you have to

know what it is!!

NiCl2 NaBr

CoF3

KNO3

BaSO4

CO2

H2O

SO2

P2O5

HCl (aq)

HI (aq)

CH2OH

CH3CH2CH3

H2SO4 (aq)

H3PO4 (aq)

Ionic Covalent

Organic

Binary acids

Oxo-acids

Polyatomic Ions

SO42-

PO43-

NO-

Practice on Ionic Charges

• What are the common charges of ions the following elements:

• potassium

• sulfur

• chlorine

• magnesium

• nitrogen

• cobalt

• silver

• zinc

• cadmium55

Many of these can be determined by their location on the periodic table. Others

cannot!

Writing Ionic Formulas

Any binary ionic formula has two parts. A cationand an anion. A metal and a non-metal can

usually form only one compound.

Na+ F-

To find the formula for…

NaF

Mg2+ Cl-

MgCl2

Notice that in both

cases, the charges cancel

Writing Ionic Formulas – “Short Cut”

Na+ F-

Na F

Mg2+ Cl-

Mg Cl2

Think of the “short-cut” method is a bit like cross-multiplication.

Use the charge of

the metal to give you the subscript of the non-metal

Writing Ionic Formulas – “Short Cut”

Fe2+ O2-

Fe2O2

If you use the “short-cut” method, you must reduce the subscripts to the lowest whole number ratio

FeOReduce

This “reduce” rule is for ionic compounds. You do not want to “reduce” for covalent

compounds.

Metal vs Nonmetal Ions

Metal ions are named the same as neutral metal atoms.

Na: sodium atom

Na+: sodium ion

Nonmetal atoms and nonmetal ions differ in the suffix. -ide is added.

F: fluorine atom

F-: fluoride ion

Metals tend to lose

electrons to become stable ions

Non-metals tend to gain electrons to

become stable ions

Common Charges for Main Group Ions

Most of these charges can be deduced by looking at the group number

Common Charges of the d-block

These are the most commoncharges. Other charges are possible

Can also be

Cu+

Can also be

Cr6+

Can

also be Co3+

Ionic Compounds

NaF Sodium Fluoride

MgCl2 Magnesium Chloride

FeO Iron (II) Oxide

Fe2(SO4)3 Iron (III) Sulfate

Name of metal + name of non-metal ion

Metals with more than one possible

charge must be specified explicitly

Polyatomic ions are treated like

any other monoatomic ion

Fe3+

Fe2+

Polyatomic Ions

Some common polyatomic ions

Polyatomic ions are just…well…basically like they sound. Ions

that have many atoms. In reality polyatomic ions are actually

covalent molecules with an overall charge.

(draw the Lewis structure for nitrate)

OH- hydroxideCH3COO- acetateNH4

+ ammoniumCN- cyanide

CO32- carbonate

NO3- nitrate

PO43- phosphate

SO42- sulfate

ClO3- chlorate

oxoanions

Oxoanion Nomenclature

1 More oxygen per_____ate

Most common _____ate

1 Less oxygen _____ite

Still fewer hypo_____ite

• What is the name of NaClO?

• What is the formula for sodium chlorate?

• What is the name of FePO4?1414

Writing Ionic Formulas – Polyatomic Ions

Treat polyatomic ions the same as monoatomic ions when forming compounds. Polyatomic ions stay together as a

unit.

Use “()” for multiplepolyatomic ions only

Fe2+ PO43-

Fe3(PO4)2

Na+ NO3- Na(NO3)

Common Confusion

Nitrate

NO3-

Nitride

N3-

Nitrite

NO2-

Sulfate

SO42-

Sulfite

SO32-

Sulfide

S2-

Phosphate

PO43-

Phosphite

PO33-

Phosphide

P3-

MonoatomicPolyatomic

Examples of Ionic Formulas

• Write the formulas of compounds made by the following pairs of ions.

• Ba + Cl

• Ba + O

• Fe + Cl (HHMMM…what’s the trick here?)

• Na + O

• Mg + NO3

• Zn + F

• Al + S

1717

Ionic formulas

Ionic compounds

• Systematic names

– Names given using established nomenclature system

• Common names

– Names given before nomenclature system was devised

– Many involved in mining / minerals

• Examples

– Lime, calcium oxide CaO

– Galena, lead (II) sulfide PbS

– Fluorite, calcium fluoride CaF2

Ionic Compounds

• Write formulas for the following names:

– aluminum bromide

– titanium(IV) chloride

– chromium(III) sulfide

• Write names for the following formulas:

– Ba3N2

– K2S

– MnF2

1919

Binary Covalent Compounds: 2 Nonmetals

Why do we need prefixes in covalent

compounds?

Write the most metallic element first

Use prefixes to indicate number of

atoms

Never use mono for first element in name

•Mono: 1 (monosyllabic)

•Di: 2

•Tri: 3 (triathlon)

•Tetra: 4 (tetris)

•Penta: 5 (pentagon)

•Hexa: 6 (hexagon)

•Hepta: 7

•Octa: 8 (octagon)

•Nona: 9

•Deca: 10 (decathlon)

2020

Binary Covalent Compounds

• Write formulas for the following names:

– silicon tetrachloride

– carbon monoxide

– tetraphosphorus hexaoxide

• Write names for the following formulas:

– N2O4

– Cl2O7

– SF6

– H2S

– H2Se

– NO2

Although covalent, it is treated as H+ + S2-

Are the following names/formulas correct?

• Iron trichloride

• Magnesium monoxide

• Nitrogen oxide

• NaO

• Iron chloride

• Ferric (III) chloride

• Tin trichloride

• Iron chloride

• Sodium monoxide

• Iron (3) chloride

• Magnesium (II) oxide

• Carbon Sulfate

Acids and Bases

• Hydrogen cation (H+), also called the proton

• Hydroxide anion (OH-)

• Acid: substance that produces H+ in water

– HCl, HNO3, H2SO4, H3PO4

– HCl dissolves in water � H+ (aq) + Cl- (aq)

• Base: substance that produces OH- in water

– NaOH, KOH, Ba(OH)2– NaOH dissolves in water � Na+ (aq) + OH- (aq)

Binary Acids (H+ + anion)

Binary acids: acids with an H+ and an anion.

• Name the following acids:

• HBr (aq)

• HCl (aq)

• HI (aq)

• HF (aq)

• HCN (aq)

2424

hydro_____ic acid

Name of anion

Binary Acids Oxoacids

2626

per_____ate per_____ic acid

_____ate _____ic acid

_____ite _____ous acid

hypo_____ ite hypo_____ous acid

Oxoanion Acid

The name and suffix of the oxoanion determines the name of the acid

SO32-

sulfite

H2SO3

sulfurousacid

Oxoacid Nomenclature Nomenclature

•diphosphorustetraoxide

•XeF4

•carbon tetrachloride

•aluminum oxide

•SnO2

•PbF2

•copper (II) nitrate

•chromium (VI) oxide

•H2SO3 (aq)

•calcium carbonate

•H2CO3 (aq)

•iron (III) oxide

•SiO2

•TiCl3•sulfurous acid

•P4O10

•carbonic acid

•Cr2O3

•lead (II) chromate

•HBr (aq)

•hydrofluoric acid2828

Nomenclature Answers

•P2O4

•xenon tetrafluoride

•CCl4•Al2O3

•tin (IV) oxide

•lead (II) fluoride

•Cu(NO3)2•CrO3

•sulfurous acid

•CaCO3

•carbonic acid

•Fe2O3

•silicon dioxide

•titanium (III) chloride

•H2SO3 (aq)

•tetraphosphorusdecoxide

•H2CO3 (aq)

•chromium (III) oxide

•PbCrO4

•hydrobromic acid

•HF (aq)