Types of Compounds

Chapter 5

Objectives 5.1

• 5.1 Apply ionic charge to writing formulas

• 5.1 Apply formulas to name ionic compounds

• 5.1 Interpret the information in a chemical formula

Ionic “Bonds”

• Instead of Formula’s: Ratio’s

• Some atom’s want more electrons than the other wants to give up

• So they bind to two, or three

• Example: Li and O, Li wants to give up only 1 electron, but O wants 2 electrons

Practice Question

• What ratio of Mg and N are needed to make an Ionic compound that has a neutral charge?– Draw a Lewis electron dot diagram for N– Draw a Lewis electron dot diagram for Mg

• What ratio of Na and Br are needed to make an Ionic compound that has a neutral charge?

+1+2 General Ionic Charges -1-2-3

Ionic Nomenclature

• Only use Ionic Nomenclature when dealing with Ionic compounds– An ionic compound is formed when a metal

and a non metal come together and electrons are completely lost and gained

Fixed Oxidation State

• Some Metals will always lose the same amount of electrons. These metals have Fixed Oxidation States

• Alkali Metals = +1

• Alkaline Earth Metals = +2

• Aluminum = +3

Ionic Nomenclature

• Binary Compounds of Metals with Fixed Charges: Given Formula, Write the Name

• The order for names in a binary compound is first the cation, then the anion.

• Use the name of cation with a fixed oxidation state directly from the periodic table.

• The name of the anion will be made from the root of the element's name plus the suffix "-ide."

Practice Naming

• What is the name of the following?

• MgO

• Magnesium Oxide

• NaF

• Sodium Flouride

• CaS

• Calcium Sulfide

Ionic Nomenclature

• Given Name, Write Formula• The order in a formula is first the cation, then the

anion. • You must know the charges associated with

each cation and anion. • The sum of the positive charge and the sum of

the negative charges MUST add up to zero. • You MAY NOT adjust the charges of the cations

or anions to get a total charge of zero. • You MAY adjust the subscripts to get a total

charge of zero.

CATIONCATION + + ANIONANION ---> --->

COMPOUNDCOMPOUND

CATIONCATION + + ANIONANION ---> --->

COMPOUNDCOMPOUND

A neutral compound A neutral compound requiresrequires

equal number of + equal number of + and - charges.and - charges.

A neutral compound A neutral compound requiresrequires

equal number of + equal number of + and - charges.and - charges.

COMPOUNDS FORMED FROM IONS

COMPOUNDS FORMED FROM IONS

NaNa++ + Cl + Cl- - --> NaCl--> NaCl

Formulas of Ionic Compounds

Formulas of ionic compounds are determined from the charges on the ions

atoms ions

–

Na + F : Na+ : F : NaF

sodium + fluorine sodium fluoride formula

Charge balance: 1+ 1- = 0

Hint

• Cross the charges to find the amount you need.

• If it can be reduced, then do so– Ie if both are 2, then it is 1

Ionic Nomenclature

• What is the formula of the following?

• Potassium Oxide

• K2O

• Strontium Chloride• SrCl2

• Magnesium Nitride• Mg3N2

Ionic Nomenclature

• Potassium Phosphide• K3P

• Magnesium Sulfide• MgS• Radium Flouride• RaF2

Variable Charges

• The transition metals have variable charges, they are happy with losing a variety of electrons– This is because they can also lose some of

there D electrons and be stable

Transition Metals

Elements that can have more than one possible

charge MUST have a Roman Numeral to

indicate the charge on the individual ion.

1+ or 2+ 2+ or 3+

Cu+, Cu2+ Fe2+, Fe3+

copper(I) ion iron(II) ion

copper (II) ion iron(III) ion

Variable Charges

• Formula to Name• 1) Find the charge of the cation by

– Finding total charge of anion and dividing by number of cations

• Example: FeCl3– We have 3 Chlorines, each has a -1 charge– The Fe needs to be +3 to balance it out

• 2) Say the cation with its Roman Numeral– Iron (III) Chloride

Variable Charges

• What is the name?• AuF3

• Gold (III) Flouride• AgF• Silver (I) Flouride• PbO2

• Lead (IV) Oxide

Variable Charges

• SnF2

• Tin (II) Flouride• MnO2

• Manganese (IV) Oxide• CrN• Chromium (III) Nitride• Sn3N4

• Tin (IV) Nitride

Variable Charges

• Name to Formula

• The Roman Numeral tells you the charge

• Balance the formula

• Iron (III) Oxide– Fe has a +3 charge as denoted by the III– Oxygen always has a -2 charge– Cross them (Balance)– Fe2O3

Variable Charge

• What’s the formula?

• Lead (IV) Sulfide• PbS2

• Copper (I) Chloride

• CuCl

• Silver (I) Nitride

• Ag3N

Variable Charge

• Gold (III) Arsenide

• AuAs

• Tin (II) Bromide• SnBr2

• Cobalt (III) Oxide• Co2O3

Writing a Formula

Write the formula for the ionic compound that will form between Ba2+ and Cl.

Solution:

1. Balance charge with + and – ions

2. Write the positive ion of metal first, and the

negative ion Ba2+ Cl

Cl3. Write the number of ions needed as

subscripts BaCl2

Learning Check

Write the correct formula for the compounds containing the following ions:

1. Na+, S2-

a) NaS b) Na2S c) NaS2

2. Al3+, Cl-

a) AlCl3 b) AlCl c) Al3Cl

3. Mg2+, N3-

a) MgN b) Mg2N3 c) Mg3N2

Solution

1. Na+, S2-

b) Na2S

2. Al3+, Cl-

a) AlCl3

3. Mg2+, N3-

c) Mg3N2

Naming CompoundsNaming Compounds

• 1. Cation first, then anion

• 2. Monatomic cation = name of the element

• Ca2+ = calcium ion

• 3. Monatomic anion = root + -ide

• Cl = chloride

• CaCl2 = calcium chloride

Binary Ionic Compounds:Binary Ionic Compounds:

Naming Binary Ionic Compounds

Examples:

NaCl

ZnI2

Al2O3

sodium chloride

zinc iodide

aluminum oxide

Learning Check

Complete the names of the following binary compounds:

Na3N sodium ________________

KBr potassium ________________

Al2O3 aluminum ________________

MgS _________________________

Mixed Review

• Given the name, write the formula

• Given the formula, write the name

• 1) Sodium Oxide

• 2) Lead (II) Nitride

• 3) Cesium Iodide

• 4) RbF

• 5) AuO

Mixed Review

• 6) SrCl2

• 7) CoS

• 8) Ag2Se

• 9) Manganese (IV) Chloride

• 10) Radium Nitride

Answers to Review

• 1) Na2O• 2) Pb3N2

• 3) CsI

• 4) Rubidium Flouride

• 5) Gold (II) Oxide

Answers to Review

• 6) Strontium Chloride

• 7) Cobalt (II) Sulfide

• 8) Silver (I) Selenide• 9) MnCl4• 10) Ra3N2

Objectives 5.2

• 5.2 Apply organic nomenclature to name hydrocarbons

• 5.2 Distinguish among allotropes of an element.

• 5.2 Apply formulas to name molecular compounds

Naming Molecular Compounds

CH4 methaneBCl3 boron trichloride

CO2 Carbon dioxide

All are formed from two or more nonmetals.

Ionic compounds generally involve a metal and nonmetal (NaCl)

Molecular (Covalent) Nomenclaturefor two nonmetals

• Prefix System (binary compounds)

1. Less electronegative atom comes first.

2. Add prefixes to indicate # of atoms. Omit mono- prefix on the FIRST element. Mono- is OPTIONAL on the SECOND element (in this class, it’s NOT optional!).

3. Change the ending of the second element to -ide.

PREFIXmono-di-tri-tetra-penta-hexa-hepta-octa-nona-deca-

NUMBER123456789

10

Molecular Nomenclature Prefixes

• CCl4

• N2O

• SF6

• carbon tetrachloride

• dinitrogen monoxide

• sulfur hexafluoride

Molecular Nomenclature: Examples

• arsenic trichloride

• dinitrogen pentoxide

• tetraphosphorus decoxide

• AsCl3

• N2O5

• P4O10

More Molecular Examples

Learning Check

Fill in the blanks to complete the following names of covalent compounds.

CO carbon ______oxide

CO2 carbon _______________

PCl3 phosphorus _______chloride

CCl4 carbon ________chloride

N2O _____nitrogen _____oxide

Learning Check

1. P2O5 a) phosphorus oxide

b) phosphorus pentoxide

c) diphosphorus pentoxide

2. Cl2O7 a) dichlorine heptoxide

b) dichlorine oxide

c) chlorine heptoxide

3. Cl2 a) chlorine

b) dichlorine

c) dichloride

A flow chart for naming binary compounds.

Mixed Practice

1. Dinitrogen monoxide

2. Potassium sulfide

3. Copper (II) nitrate

4. Dichlorine heptoxide

5. Chromium (III) sulfate

6. Iron (III) sulfite

7. Calcium oxide

8. Barium carbonate

9. Iodine monochloride

Mixed Practice

1.1. BaIBaI22

2.2. PP44SS33

3.3. Ca(OH)Ca(OH)22

4.4. FeCOFeCO33

5.5. NaNa22CrCr22OO77

6.6. II22OO55

7.7. Cu(ClOCu(ClO44))22

8.8. CSCS22

9.9. BB22ClCl44

NONO33--

nitrate ionnitrate ion

NONO22--

nitrite ionnitrite ion

Polyatomic Ions

Polyatomic Ions

You can make additional polyatomic You can make additional polyatomic ions by adding a Hions by adding a H++ to the ion! to the ion!

COCO33 -2-2 is carbonate is carbonate

HCOHCO33–– is hydrogen carbonate is hydrogen carbonate

HH22POPO44–– is dihydrogen phosphate is dihydrogen phosphate

HSOHSO44–– is hydrogen sulfate is hydrogen sulfate

Polyatomic IonsPolyatomic Ions

Ternary Ionic Nomenclature

Writing Formulas

• Write each ion, cation first. Don’t show charges in the final formula.

• Overall charge must equal zero.– If charges cancel, just write symbols.– If not, use subscripts to balance charges.

• Use parentheses to show more than one of a particular polyatomic ion.

• Use Roman numerals indicate the ion’s charge when needed (stock system)

Monatomic Ions

Examples of Older Names of Cations formed from Transition Metals

(you do not have to memorize these)

Diatomic Elements

• Dr. HOFBrINCl

• These elements are found naturally as two elements and do NOT use a prefix

• O2 is Oxygen, not DiOxygen

Allotropes

• Molecules of a single element that different in molecular structure or crystalline structure– Oxygen and Ozone– Diamond, Graphite, Charcoal, Fullerenes,

Acetylenic

Hydrocarbons

• Composed of Carbon Chain and hydrogens (functional groups discussed later)

• Methane Hexane

• Ethane Heptane

• Propane Octane

• Butane Nonane

• Pentane Decane