Nomenclature 12-13.ppt

Substances

Element Compound

Atom Diatomic

Molecule Molecule Ionic Compound

Acid

Element

Two types: Atom & Diatomic Molecule

Type:

Identification:

Atom

Contains only one atom

Example:

Au gold

9.2 Diatomic Molecules

• Diatomic Molecules – 2 atom molecule

of one element.

– Formula

• H₂, O₂, N₂, F₂, Cl₂, Br₂, I₂ • HON FClBrI

– Name

•

Chemical Bond

– attractive force between atoms or ions that binds them together as a unit

– bonds form in order to…

• increase stability

We now know that there are two

main types of chemical bonding;

• ionic bonding

Ionic Bonding

• In ionic bonding, electrons are completely transferred from one atom to another.

• In the process of either losing or gaining

negatively charged electrons, the reacting atoms form ions.

• The oppositely charged ions are attracted to

each other by electrostatic forces, which are the basis of the ionic bond.

Covalent (Molecular) Bonding

– Co- means together

– Valent- electrons in the outermost shell

• Covalent bonding occurs when two (or more) elements SHARE electrons.

• Covalent bonding occurs because the atoms in the compound have a similar tendency for

electrons (generally to gain electrons). • This most commonly occurs when two

Molecules

Hydrogen And oxygen

water

Chocolate fat _DNA

CHEMICAL

FORMULA

molecular

formula

formula

unit

IONIC

COVALENT

CO

CO

₂

₂

NaCl

Writing Formulas of Covalent Molecules

Covalent Molecules

contain two types of nonmetals

Key: FORGET CHARGES

What to do:

•Give the name of the less electronegative element first

•Use Greek prefixes to indicate how many atoms of each element •Don’t use “mono” on first element

•Ending of second element changes to –ide

•Normally, do not have double vowels when writing names (ao oo)

Prefixes you should know:

Writing Formulas of Covalent Molecules

EXAMPLES:

carbon dioxide CO

dinitrogen trioxide N₂O₅

carbon tetrachloride NI₃

CO₂

carbon monoxide N₂O₃

dinitrogen pentoxide CCl₄

More Practice

1. ________________ diarsenic trisulfide 2. ________________ sulfur dioxide

3. P₂O₅ ____________________ 4. ________________ carbon dioxide

5. N₂O₅ ____________________ 6. H₂O ____________________

As₂S₃

SO₂

diphosphorus pentoxide

CO₂

dinitrogen pentoxide

Molecular Compounds

N₂O dinitrogen monoxide N₂O₃ dinitrogen trioxide N₂O₅ dinitrogen pentoxide ICl iodine monochloride ICl₃ iodine trichloride

Metal + Nonmetal?

Formula  Name?

Ionic

Covalent Two Nonmetals?

Multiple _Single

Use Prefixes!!! *Mono* Hexa Di Hepta Tri Octa Tetra Nona Penta Deca

1. Write name of cation (metal)

2. Determine the charge on the metal by balancing the (-) charge from the anion

3. Write the charge of the metal in Roman Numerals and put in parentheses

4. Write name of anion

(Individual anions need –ide ending!)

Steps 1 & 4 ONLY d,f-block

Pb,Sn

Columns 1, 2, 13 Ag+_{, Zn}2+

Name  Formula?

No Prefixes? Prefixes?

1. Determine the ions present and the charge on each

(Roman Numeral = cation charge, otherwise use PT)

2. Balance formula (criss-cross) 3. Reduce subscripts (if needed)

1. FORGET CHARGES!!! 2. Use prefixes to determine

subscripts

3. Do NOT reduce subscripts!

Acids are…

• Compounds that give off

hydrogen ions when dissolved in

water. (aqueous (aq))

• Will start the formula with H.

• There will always be some

Hydrogen next to an anion.

Rules for Naming acids

1)

If the anion attached to

hydrogen ends in

-ide

, put the

prefix hydro- and change -

ide

to

-ic acid

•

_{HCl - hydrogen ion and chloride}

ion =

hydro

chlor

ic acid

•

H

S hydrogen ion and sulfide

Naming Acids

•

_{If the anion has oxygen in it, then it ends in}

-ate or -ite

2) change the suffix -

ate

to -

ic acid

(use no

prefix)

•

Example: HNO

Hydrogen and nitr

ate

ions

= Nitr

ic acid

3) change the suffix -

ite

to -

ous acid

(use no

prefix)

•

Example: HNO

Hydrogen and nitr

ite

ions

Naming Acids

Anion ending

____-ide

____-ate

____-ite

Acid name is…

hydro-___-ic acid

_____-ic acid

Naming Practice:

•

_HF

•

H

P

•

H

SO

•

H

SO

Naming Practice:

•

_{HF hydrofluoric Acid}

•

H

P hydrophosphoric Acid

•

H

SO

sulfuric acid

•

H

SO

sulfurous acid

Writing Acid Formulas –

• Hydrogen will always be listed first

• The name will tell you the anion

• Be sure the charges cancel out

• Starts with prefix hydro?- there is

no oxygen, -

ide

ending for anion

Write formulas for these:

• hydroiodic acid

• acetic acid

• carbonic acid

Helpful to remember...

1. In an ionic compound, the net ionic

charge is zero (criss-cross method)

2. An

-ide

ending generally indicates a

binary compound

3. An

-ite

or

-ate

ending means there is

a polyatomic ion that has oxygen

Helpful to remember...

5. A Roman numeral after the name

of a cation is the ionic charge of

the cation

6.

How to remember acids: If you “ATE”

gum it would be “IC-ky”, if you “b-ITE” gum

it would be “delici-OUS” but if “-ide drink