Chapter 7 - Chemical Formulas and Chemical Compounds

Hemoglobin

Monotomic IonsDefinition Steps in

Creating the Formula

How Do You Name It?

Example

Monatomic Ions

Ions formed from a single atom. Main group ions form to a noble gas configuration

No formulas—just ions!!

For cations: The elements name.For anions: The ending of the name is dropped and the ending –ide is added.

Cation Ex. Ca is calcium; Ca+2 is CalciumAnion Ex. F is flourine; F- is flouride

Binary Ionic CompoundsDefinition Steps in Creating

the Formula How Do You Name It?

Example

Binary Ionic Compounds

Compounds composed of two elements, the total charge must be equal to zero.

1. Write the symbols and charges of the ions side by side, cation first.Al3+ O2−2. Cross over the charges by using the absolute value of each ion’s charge as the subscript for the other ion. Make sure that the total charges now add up to zero.Al23+ O32−3. The reason for this is so that the number of electrons that are being given by the cation can be received by the anion(s). Al2O3

1. Use the name of the cation first2. Then use the anion name, but drop the ending and add –ideNote: You are basically just naming the monatomic ions separately and then putting them together

Al2O3Aluminum Oxide

EXAMPLE

• Write the formula for the binary ionic compounds formed between the following elements:

• Zinc and iodine• Sodium and sulfur• Aluminum and nitrogen• Name: AgCl• Name: CaCl2

Transition metals

DefinitionDefinition Steps in Steps in Creating the Creating the FormulaFormula

How Do You How Do You Name It?Name It?

ExampleExample

Transition Transition MetalsMetals

D-block D-block elementselements

Transition Transition metals can metals can have more have more than one than one charge (No charge (No formulas)formulas)

The name The name won’t change won’t change (ex. Fe=iron= (ex. Fe=iron= iron no matter iron no matter what the what the charge)charge)

PbClPbCl22

Lead (II) Lead (II) chloridechloride

Pb(SOPb(SO44))22

Lead (IV) Lead (IV) Sulfate Sulfate

EXAMPLESEXAMPLES

Write the formula and give the name for Write the formula and give the name for the compounds that form between:the compounds that form between:– Cu(2+) and Br (-)Cu(2+) and Br (-)– Sn(2+) and F(-)Sn(2+) and F(-)– Hg(2+) and S(2-)Hg(2+) and S(2-)

Name: Name:

-- CuO-- CuO

-- FeS-- FeS

Compounds With Polyatomic Ions

Definition Steps in Creating the Formula

How Do You Name It?

Example

Compounds containing Polyatomic Ions

Ionic compounds that use one or two positive or negative polyatomic ions to form ionic compounds

Another note: Are produced by the loss of hydrogen ions (H+) from oxyacids:

Sulfuric acid H2SO4

SulfateSO42−

You basically use the same steps as with putting two monatomic ions together.

THE TOTAL POSITIVE CHARGE WILL BALANCE THE TOTAL NEGATIVE CHARGE.

Except in this case, you won’t be changing the editing of the oxyanion (it stays –ate, or –ite.)

Al+3 bonding with (SO3)-1

Gives you

Al(SO3)3 called

Aluminum Sulfate

EXAMPLE

Write the formula for: Copper (II) Sulfate Potassium Sulfide Potassium Perchlorate

Give the names for: Ca(OH)2

FeCrO4

MOLECULAR COMPOUNDSMOLECULAR COMPOUNDSDefinitionDefinition Steps in Creating Steps in Creating

the Formulathe Formula How Do You Name It?How Do You Name It? ExampleExample

Molecular Molecular CompoundsCompounds

MolecularMolecular

CompoundsCompounds

are covalently are covalently

bonded units. bonded units.

You will usually be You will usually be given the formula given the formula and then you can and then you can find the oxidation find the oxidation numbers of the rest numbers of the rest of the atoms from of the atoms from there, but you would there, but you would normally draw the normally draw the Lewis structureLewis structure

Two ways:Two ways:

1. The less 1. The less electronegative electronegative element is given first. element is given first. It is given a prefix (ex. It is given a prefix (ex. di, tri, etc.) only if it di, tri, etc.) only if it contributes more than contributes more than one atom to a one atom to a molecule.molecule.

Ex. CarbonEx. Carbon

2. The second element 2. The second element is named by is named by combining:combining:

a. a prefix indicating a. a prefix indicating the number of atoms the number of atoms contributed by the contributed by the element,element,

b. the root of the b. the root of the name of the second name of the second element, andelement, and

c. the ending c. the ending –ide.–ide. Ex. DioxideEx. Dioxide

Ex. CCl4Ex. CCl4

CarbonCarbon

TetrachlorideTetrachloride

Ex. P5O2Ex. P5O2

Penta-Penta-

PhosphorusPhosphorus

Dioxide Dioxide

EXAMPLESEXAMPLES

Name the following:Name the following: SOSO33

IClICl33 PBrPBr55

Write the formulas for:Write the formulas for: Phosphorus tetraiodidePhosphorus tetraiodide Dinitrogen trioxideDinitrogen trioxide

Binary AcidsBinary AcidsDefinitionDefinition Steps in Creating the Steps in Creating the

FormulaFormula How Do You Name It?How Do You Name It? ExampleExample

Binary Binary AcidsAcids

Consist of 2 Consist of 2 elements, elements, usually usually hydrogen hydrogen and one of and one of the halogensthe halogens

Will always Will always have one have one hydrogen hydrogen bonded to a bonded to a highly highly electronegative electronegative atom to formatom to form

In general, if the In general, if the anion ends in anion ends in ––ideide, ,

the acid name will the acid name will end in end in –ic –ic and and begin with the begin with the prefix prefix hydro-.hydro-.

Ex. HClEx. HCl

Hydrochloric Hydrochloric AcidAcid

EXAMPLEEXAMPLE

Write the formula for:Write the formula for: HIHI HFHF

Oxyacids

DefinitionDefinition Steps in Creating the Steps in Creating the FormulaFormula

How Do You Name It?How Do You Name It? ExampleExample

OXYACIDS Acids that Acids that contain contain hydrogen, hydrogen, oxygen, and a oxygen, and a third element third element (usually a (usually a nonmetal).nonmetal).

Will always have Will always have one hydrogen one hydrogen bonded to a bonded to a negatively negatively charged group--charged group--likely a oxyanion likely a oxyanion (ex. NO(ex. NO33-) -)

If the anion ends in If the anion ends in -ate the acid name -ate the acid name will end as -ic. If will end as -ic. If the anion ends in -the anion ends in -ite the acid will end ite the acid will end as -ous.as -ous.

Sulfuric Sulfuric acid – acid – HH22SOSO44

EXAMPLESEXAMPLES

Write the formula for:Write the formula for: Phosphoric acidPhosphoric acid

Name:Name: HH22SOSO44

SALTSDefinitionDefinition Steps in Creating the Steps in Creating the

FormulaFormula How Do You Name It?How Do You Name It? ExampleExample

SALTSSALTS An ionicAn ionic

compound compound

composed of composed of

a cation and a cation and

the anion the anion

from an acid. from an acid.

The oldThe old

definition was definition was

the product of the product of

an acid and a an acid and a

base reacting to base reacting to

form a salt and form a salt and

water:water:

HCl + NaOH → HCl + NaOH → NaCl + H2ONaCl + H2O

The anion is The anion is named by adding named by adding the word the word hydrogenhydrogen or the prefix or the prefix bibi- to - to the anion name:the anion name:

HCO3−HCO3−

Hydrogen Hydrogen carbonate ioncarbonate ion

Bicarbonate ionBicarbonate ion

Ex. NaHCO3Ex. NaHCO3

SodiumSodium

bicarbonatebicarbonate

(baking(baking

soda)soda)