Atoms want 8ve- to be stable “happy”

Chemical Bonds / Formulas Atoms bond to become stable or

“happy” – octet rule (full valence shell) When they bond they form

compounds. Each compound has a special

formula Subscripts show how many of each

element is in the compound

FORMULASMgCl2

The subscript is the number at the bottom of a formula.

There is 1- Mg & 2 – Cl Never use 1 as a subscript!

IONIC BONDbond formed between

two ions by the transfer of electrons

Ions Atom that gains or loses electrons

to become stable “happy” Cation: loses e- to form (+)

charged ion Anion: gains e- to form (-)

charged ion

Formation of Ions from Metals

Ionic compounds result when metals react with nonmetals

Metals lose electrons to form a positive charge Nonmetals gain electrons to form a negative

charge

Metals: Nonmetals: Na+ N -3

Ca+2 S -2

Al+3 Br -

IONIC BONDS Bonds form from the (+) & (-)

charges. Form a network of ions. – very

strong bonds. Conduct electricity when

melted or dissolved in water.

Writing Ionic Formulas – binaryRepresentative metals

Calcium & oxygen

Write the metal ion Ca +2

Write the nonmetal ion O -2

If charges cancel – ratio is 1:1 ( 1 of each)

CaO

Magnesium & chlorine

Write the metal ion Mg +2

Write the nonmetal ion Cl -

If charges DO NOT cancel – drop & swap

MgCl2

Writing Ionic Formulas – binaryTransition metals

Ion charges change – an element can have more than one ion charge

The charge is given as a ROMAN NUMERALEx: Iron (II) Fe+2 / Iron (III) Fe+3

Gold (I) Au + / Gold (III) Au+3

You will never have to memorize all the charges each transition metal forms – the charges will be given to you !!!!!

Practice Magnesium & iodine

Strontium & bromine

Barium & nitrogen

Aluminum & phosphorus

Naming Ionic Formula - binary Representative Metals

Name the metalChange the ending of the

nonmetal to – ide

MgCl2 - magnesium chlorideAlP - aluminum phosphide

Cl – chloride C - carbideF – flouride Se - selenideI – iodide N – nitrideP – phosphide S – sulfideBr – bromide O – oxide

Transition MetalsName the metal & Include the

charge using a Roman Numeral

Ex: Iron (II) Fe+2 / Iron (III) Fe+3

Gold (I) Au + / Gold (III) Au+3

Change the ending of the nonmetal ending to –ide

Fe +2 Cl - iron (II) chloride

Au + O -2 gold (I) oxide

Practice CaBr2

Na3N

BCl3

MgO

FeCl3

Ni3N

ZnO

FeS

Ternary Ionic Bonds – contain Polyatomic Ions

Polyatomic ion : a group of (covalently) bonded nonmetals that form a charge.

Act as a single ion in an ionic bond

Have special names that DO NOT CHANGE

You need to write down the polyatomic ions and their names on a sheet of paper and DO NOT LOSE IT!!!

You will use your list on all quizzes and tests!

AmmoniumNH4+

Acetate C2H3O2-

Hypochlorite ClO-

Chlorite ClO2-

Chlorate ClO3-

PerchlorateClO4-

Cyanide CN-

Hydroxide OH-

Nitrite NO2-

Nitrate NO3-

Bicarbonate/Hydrogen Carbonate HCO3-

Carbonate CO3-2

Chromate CrO4-2

Dichromate Cr2O7-2

Oxalate C2O4-2

Sulfate SO4-2

Sulfite SO3-2

Phosphite PO3-3

Phosphate PO4-3

Permanganate MnO4-

Peroxide O2-2

Writing Ionic Formulas - ternary Write the cation – all metals (only polyatomic cation

is ammonium: NH4+ )

Write the anion – all nonmetals and polyatomic ions

If charges cancel – 1:1 ratio

If charges DO NOT cancel – drop & swap You must use parenthesis if more than one

polyatomic ion is present

Practice cesium nitrate

barium sulfite

aluminum hydroxide

strontium phosphate

ammonium sulfide

Iron(III) chlorite

Zinc(II) nitrite

Gold(III) carbonate

Silver(I) phosphite

Copper(I) acetate

Naming ionic formulas - ternaryRepresentative metal Name the cation Use the same name

for the polyatomic ion

If the anion is a nonmetal – change the ending to -ide

Transition metal Name the metal and include

a ROMAN NUMERAL for the charge of the metal

Use the same name for the polyatomic ion

If the anion is a nonmetal – change the ending to -ide

Group 1 - Alkali Metals

reacts violently with water VERY reactive, one valence e-

to lose; +1 cation

Alkali metals http://www.youtube.com/watch?v=m55k

gyApYrY&safety_mode=true&persist_safety_mode=1

Group 2 - Alkaline Earth Metals

2 valence e-; +2 cation reactive

http://www.youtube.com/watch?v=m55kgyApYrY&safety_mode=true&persist_safety_mode=1

Transition Metals Groups 3-12 Ions charges change –

changes properties NOT REPRESENTATIVE!

Halogens -Group 17 -1 ions, highly reactive 7 valence e-

Noble Gases Group 18 unreactive, 8 valence e- do not form ions exist as single atoms,

don’t bond - inert

COVALENT BONDbond formed by the sharing of electrons

Covalent Compounds

Covalent compounds result when nonmetals react with nonmetals

Both nonmetals share their valence electrons to be happy – Octet Rule

Examples:CO2 SCl2

H2O CH4

Naming Covalent formulas Use prefixes to show the # of atoms of each

element in a covalent compound 1 – mono 6 - hexa 2 – di 7 - hepta 3 – tri 8- octa 4 – tetra 9 - nona 5 – penta 10 – deca

1st element – use prefixes only of the # of atoms is greater than 1

2nd element – use prefixes; change ending to – ide

Practice CO2

N3F8

Se4Br9

S7O

tetraselenium nonabromide

trinitrogen octaflouride

heptasulfur monoxide

carbon dioxide

Writing Covalent formulas Use the prefix to identify how many of each

nonmetal atoms are in each molecule The prefix becomes the subscript.

Carbon Tetrahydride Disulfur Hexachloride○ CH4 S2Cl6

1) Name the following covalent compounds:a) SiF4

b) N2S3

c) H3Br7

d) S5Br9

e) H2O

2) Write the formulas for the following covalent compounds:

a) diboron hexahydrideb) nitrogen tribromidec) sulfur hexachlorided) diphosphorus pentoxide