Chemical Names & Formulas

Chapter 9

Warm Up

Take 7 min to finish Homework

Go Over

ChemQuest 21

Skill Practice 19-21

More Ionic Bonding Practice

Time to Review Ionic Bonding

IB QUIZ NEXT CLASS

This should go quick. All of this has been taught. Some of these slides you have already seen

Ionic Bonding: Between Metals and Nonmetals

Monatomic Ions Ions consisting of one atomDetermined by using the periodic table

Transition Metals - the charge must be provided

Ex.)

Fe(III) has a +3 charge

Fe(II) has a +2 charge

Reference Table 9.2, p.255 for trans. metal names and charges Stock Name vs. Classical Name

Ex) Copper(I) ion (stock name) and Cuprous ion (classical name)

Polyatomic Ions

Tightly bound group of atoms that behave as a unit and carry a charge

Treated the same as monatomic ions when writing chemical formulas and naming (also called tertiary compounds)

Ex.)(PO4)3-

(CO3)2-

Phosphate

Carbonate

Polyatomic Ions

Types of Compounds

Ionic – Metal & Non-Metal

Molecular– 2 Non-Metals

Ionic Compounds Ionic bond forms between ions (atoms w/ a

charge b/c they have extra or missing e-)– Represented by chemical formulas (or formula

units)• Ex) NaCl

– Typically solids at room temperature

Occurs between oppositely charged ions (“opposites attract”)

Include a cation & an anion

Cation = + charges

Anion = - charges

In an ionic compound, the atoms combine in ratios to balance the charges (neutral compound)

Ex.) How many Mg will react w/ S?

Mg2+ + S2- MgS

Criss-Cross Method

An easier way to determine the subscripts

Use it if it makes sense to you. Otherwise, continue balancing the charges

Criss-Cross Method: How many B will react w/ S?

B3+ & S2-

B3+ S2-+ B2S3

Notice: when you write the formula the cation (metal) goes 1st

32

Examples:

What is the formula when Al and F combine?

Al3+ & F1-

Al3+ F1-+ AlF331

Examples:

Lithium and Bromine LiBr

Calcium and Sulfur CaS

Zn (II) and Phosphorus Zn3P2

Sodium and Phosphate Na3PO4

Naming Ionic CompoundsBinary compounds - composed of 2

elements

1st write the name of the cation

2nd write the name of the anion

Replace the ending with “-ide”

Examples:

Al2O3 Aluminum OxideSodium ChlorideCalcium Oxide

Iron(II) Sulfide

Copper(II) Bromide

NaCl

CaO

FeS

CuBr2

Naming Ionic Compounds with Polyatomic Ionscomposed of 3 or more different

elements

1st write the name of the cation

2nd write the name of the polyatomic ion

Examples:

Al(NO3)3

Copper(I) Phosphate

Aluminum Nitrate

Na(OH) Sodium Hydroxide

Ca(SO4)

Fe(CrO4)

Cu3(PO4)

Calcium Sulfate

Iron(II) Chromate

Naming Race Worksheet

Second Page (Front/Back) of packet Work with ONE partner OR by yourself Do all 45 Get answers checked by me First group done:

Naming Acids

Use the template below to name acids:

Anion ending

Example Acid name Example

- ide HCl

Chloride

Hydro( )-ic acid Hydrochloric acid

- ite H2SO3

Sulfite

( ) – ous acid

Sulfurous acid

- ate HNO3

Nitrate

( ) – ic acid Nitric acid

Properties of IB

Properties

- Electrically neutral compounds

- High boiling/melting point (BP/MP) - Form crystal solids which are brittle

- Dissolve in Water

- Conduct electricity in molten or dissolved state

Ionic Compounds

Dissociate into ions when they dissolve So,

– NaCl Na+ + Cl-

– AlCl3 Al+3 + 3Cl-

Note: The number of each ion becomes a coefficient (3Cl-)

Ions have a charge, so the charge MUST be written

Write the equation when the following ionic compounds dissolve in water

MgO Na3P

Fe2O3

Mg(NO3)2

FeSO4

Work on Ionic Bonding Practice

First Page (Front/Back) of Packet

STOP

Complete any unfinished worksheets

Molecular CompoundsCompounds composed of molecules

(usually 2 or more non-metals)– Represented by molecular formulas

• Ex) H2O

– Typically exist as gasses or liquids at room temperature

Diatomic molecules– H2, N2, O2 , F2 , Cl2 , Br2 , I2

Naming Molecular Compounds

Binary molecular compounds - composed of 2 non-metals– Use prefixes to distinguish

between different compounds (Table 6.5, p.159)

– Atom which is furthest to the left is written first

Prefix Number

Mono- 1

Di- 2

Tri- 3

Tetra- 4

Penta- 5

Hexa- 6

Hepta- 7

Octa- 8

Nona- 9

Deca- 10

Examples:

SO3

Trisulfur Octiodide

Sulfur trioxide

CO Carbon Monoxide

OF6

P2Br4

S3I8

Oxygen Hexafluoride

Diphosphorustetrabromide

Examples Name the following acids

– HBr– HNO2

– H2SO4

Write the formula for the following acids

– Hydrofluoric acid

– Phosphorous acid

The Law of Definite Proportions the masses of the elements are always

in the same proportions in any sample of a chemical compound

8:1 16:1

The Law of Multiple Proportions

Comparison of the ratios of one element in 2 different compounds containing that particular element

Example: A sample of water contains 16 g of

oxygen, whereas a sample of hydrogen peroxide contains 32 g of oxygen. What is the ratio of oxygen in the two compounds?