electrostatic attraction between positive and negative ions

Ionic Bond

salt crystal NaCl

Na+

Cl-

cesiumchloride

calciumfluoride

Bond Formation:electrons are transferred from a metal atom to a nonmetal atom

e-

opposite chargesattract

e-

Formation of IonsMetals lose electrons to form a (+) charged ion called a cation

This process is called oxidation

Octet Rule:atoms gain or lose electrons in order to havethe same number of electrons as a noble gas

+ -

Group I A metals: Alkali metals (Li, Na, K….)sodium atom: Na has 11 p+ and 11 e-

sodium ion:Na+ has 11 p+ and 10 e-

+11

-11

+11-

10

all alkali metals lose one electron to form an ion with a + 1 charge

Li+

Na+ K+ Rb

+

1s22s22p63s1

1s22s22p6

Like Ne

Cs+

Group II A metals:Alkaline Earth metals ( Be, Mg,Ca..)calcium atom:ca has 20 p+ and 20 e-

calcium ion:Ca2+ has 20 p+ and 18 e-

+20

-201s22s22p63s23p64s2

+20

-181s22s22p63s23p6like Ar

all group 2a metals lose 2 e- to form an ion with a +2 charge

Mg2

+Ca2

+Ex: Ba2

+

Group III A metals: Al, Ga, In…..All lose 3 e- to form an ion with a +3 charge

Al3

+Ga3

+In3

+

nonmetals gain electrons to form (-) charged ions called anions

This process is called reduction

Group VII A: Halogens F, Cl, Br, I

fluorine atom: F has 9 p+ and 9 e- +9-91s22s22p5

fluorine ion:F- has 9 p+ and 10 e-+9-

101s22s22p6 Like NeAll group 7A elements gain 1 e- to form an ion with a -1 charge

F- Cl-

Br- I-

Group VI A: O, S, Se…..

sulfur atom:S has 16 p+ and 16 e-+16

-16

1s22s22p63s23p4

sulfur ion:S2- has 16 p+ and 18 e-+16-

181s22s22p63s23p6like Arall group 6A atoms gain 2 e- to form an ion with a -2 charge

O2- S2- Se2-

Group V A: N, P, As, Sb…All gain 3 e- to form an ion with a -3 charge

N3- P3- As3

-

Transition metals:various oxidation numbers (charges)

miscellaneous oxidation numbersHydrogen is -1 when combined with a metalzinc is +2 , Zn2+ silver is +1, Ag+

summary: memorize these

+1 +2 +3 -3 -

2

-1

No

ions

!

sodium chlorideNa+ Cl- NaCl

calcium fluoride

Ca2+ F- CaF2

aluminum oxide

Al3+ O2- Al2O3

zinc sulfideZn2+ S2- Zn

Snot Zn2S2ferric chlorideFe3+ Cl- FeCl3

tin (IV) oxide

Sn4+ O2-

SnO2 not Sn2O4

1. lead (II) iodide 2. potassium nitride

3. silver bromide 4. cadmium hydride

5. Chromium (III) oxide6. Copper (II) sulfide

Pb2+ I-PbI

2 K+ N3- K3N

Ag+ Br- AgBr Cd2+ H-

CdH2

Cr3+ O2- Cr2O3

Cu2+

S2-

CuS

7. sodium oxideNa+ O2- Na2O

8. aluminum fluorideAl3+ F- AlF3

9. iron (II) phosphideFe2+ P3- Fe3P2

10. zinc chloride Zn2+ Cl-

ZnCl2

NAMING BINARY IONIC COMPOUNDSRule: Name the metal, then the nonmetal; change ending to –ide; if the metal has more than one oxidation number, use Roman numeralsKI potassium

iodide Ca3N2calcium nitride

BaCl2barium chloride NaH sodium

hydride

HgCl2

mercury (II) chloride

Hg2+ Cl-

Fe2O3 Fe3+ O2- iron (III) oxide

PbO2 Pb4+ O2- lead (IV) oxide

1. AlBr3aluminum bromide

2. AgF silver fluoride

3. CaS calcium sulfide

4. FeCl2iron (II) chloride

5. Zn3P2zinc phosphide

6. MgOmagnesium oxide

7. CoBr3cobalt (III) bromide

8. CuS copper (II) sulfide

9. BaI2Barium iodide

Ternary Ionic CompoundsAll contain a polyatomic ion

ion name ion name

NO3-

CO32-

NO2-

HCO3-

SO4

2- ClO-

SO3

2- ClO2

-

PO43-

ClO3-

PO33-

ClO4-

nitratenitritesulfatesulfite

phosphatephosphite

Noo

o

carbonatebicarbonatehypochlorite

chloritechlorate

perchlorate

ion name ion name CrO4

2- CN-

Cr2O7

2- OH-

MnO4

- NH4

+

C2H3O2-

chromatedichromate

cyanide

permanganate

acetate

hydroxideammonium

writing formulas:

magnesium sulfateMg2

+SO4

2

-MgSO4

sodium acetateNa

+C2H3O

2-

NaC2H3O2

potassium carbonateK+

CO32- K2CO3

ammonium nitriteNH4

+NO2

- NH4NO2

Fe3

+NO3

- Fe NO3 3

iron (III) nitrate

copper (II) sulfateCu2

+SO4

2

-CuSO

41. Lead (II) chloritePb2

+ ClO2- Pb

(ClO2)22. calcium hydroxide

Ca2

+OH

-

Ca OH 2

NH4+

Cr2O72- NH4

ammonium dichromate

Cr2O72

3. silver sulfiteAg+

SO32-

4. potassium permanganateK+ MnO4

- KMnO4

3. mercury (II) phosphate Hg2+ PO4

3-Hg3(PO4)

2

Ag2SO3

5. ammonium perchlorateNH4+ ClO4

- NH4ClO4

4. aluminum acetate

5. lithium chromateLi+ CrO4

2-

7. tin (IV) sulfate

Zn2+

HCO3-

6. zinc bicarbonateZn(HCO3)

2

Al3+

C2H3O2-

Sn4+ SO4

2-Sn(SO4)2

Al(C2H3O2)3

Li2CrO4

Rule: Name cation then the anion; use Romannumerals for metals with multiple oxidation numbers

Al(NO3)3aluminum nitrate

NaClO3

sodium chlorate

NH4OHammonium hydroxide

Ba(CN)2

barium cyanide

CuSO4copper (II) sulfate

PbCrO4lead (II) chromate

Fe (NO2)2

iron (II) nitrite

Sn3 (PO4)4tin (IV)

phosphateSnSnSn

PO4 3-

PO4

3-

PO43-

PO43-

-12+12

1. CaCO3calcium carbonate

2. KNO2potassium nitrite

3. Zn(C2H3O2)2 zinc acetate

4. Cr(NO3)3chromium (III) nitrate

5. AgCN silver cyanide

6. Al(ClO)3aluminum hypochlorite

7. BaSO4barium sulfate

8. FePO4iron (III)

phosphate

9. Li 2Cr2O7

10. Pb (OH)3lead (III) hydroxide

lithium dichromate

Properties of Ionic Compounds (Salts)

solid, crystalline structure

high melting point

made up of metal w/ nonmetal

hard or brittle (not malleable)

conduct electricity when melted or dissolved

nonconductor as solid

soluble in water

bonding in plain metalsmetals are malleable, ductile, shiny and good conductors because of the:

metallic bondmetal ionsIn a “sea ofelectrons”