CHAPTER 4
Ionic Bonding and Naming Ionic
Compounds
| 4.1-4.4 and 4.8
|
1
Introduction
Attractive forces that hold atoms together
in compounds are called chemical bonds.
| The electrons involved in bonding are
usually those in the outermost.
| The electrons are called VALENCE
ELECTRONS
|
2
Introduction
|
o
o
Chemical bonds are classified into two
types:
Ionic bonding results from electrostatic
attractions among ions, which are formed
by the transfer of one or more electrons
from one atom to another.
Covalent bonding results from sharing one
or more electron pairs between two atoms.
3
Electron Dot Formulas
of Atoms
|
Electron Dot structures are a
convenient bookkeeping method for
tracking valence electrons.
z
Valence electrons are those electrons
that are transferred or involved in
chemical bonding.
• They are chemically important.
4
Electron Dot Formulas
of Atoms
5
Electron Dot Structures
....
H
H
H
H
....
Li
Li
Li
Li
....
..
BB
Be
Bee
B
ee
6
....
.. ..
.
BB
B
B
....
....
..
.
.
.
...C
.
.
.
.
C
C N
C
N
.N
.N
....
.. ..
O
.. O
O
.
.O
....
....
H
H
He
Hee
H
ee
....
..
.. .. .
.
N
....F
Ne
Nee
FF . N
N
ee.
..F
..
Lewis Dot Formulas
of Atoms
|
Elements that are in the same periodic
group have the same Lewis dot
structures.
.
.
Li & Na
7
..
..
. N. & .P .
.
.
..
..
. .
. .
F & . Cl
. ..
..
Chemical Formulas
|
Chemical formula shows the chemical
composition of the substance.
z
ratio of the elements present in the molecule
or compound
He, Au, Na – monatomic elements
| O2, H2, Cl2, F2, I2, N2,Br2– diatomic molecules
| O3, S4, P8 - more complex molecules
| H2O, C12H22O11 – compounds
|
• Substance consists of two or more different
elements
8
Chemical Formulas
Compound
HCl
H2O
NH3
C3H8
9
1 Molecule Contains
1 H atom & 1 Cl atom
2 H atoms & 1 O atom
1 N atom & 3 H atoms
3 C atoms & 8 H atoms
Ionic Bonding
Formation of Ionic Compounds
|
|
1.
An ion is an atom or a group of atoms
possessing a net electrical charge.
Ions come in two basic types:
positive (+) ions or cations
•
2.
negative (-) ions or anions
•
10
These atoms have lost 1 or more electrons.
These atoms have gained 1 or more electrons.
Ions and Ionic Compounds
|
|
|
Ions are atoms or groups of atoms that possess
an electric charge.
Two basic types of ions:
Positive ions or cations
z
z
z
|
one or more electrons less than neutral
Na+, Ca2+, Al3+
NH4+ - polyatomic cation
Negative ions or anions
z
z
z
one or more electrons more than neutral
F-, O2-, N3SO42-, PO43-, HCO3- - polyatomic anions
You must know the names, formulas, and
charges of the elements and common ions in the
11handout.
|
Formation of
Ionic Compounds
12
13
Ions
|
|
Use periodic table and electron configuration to help you
figure out the charge of representative elements
They try to get a configuration that is the same as a noble
gas
11 Na
12
Mg
13
Al
14
Si
15
P
16
S
17
Cl
18
Ar
14
Configuration
Ch arg e
[Ne] 3s1
[Ne] 3s2
[Ne] 3s2 3p1
[Ne] 3s2 3p2
[Ne] 3s2 3p3
[Ne] 3s2 3p4
[Ne] 3s2 3p5
[Ne] 3s2 3p6
+1
Configuration
+ 4 or − 4
[Ne]
[Ne]
[Ne]
[Ne] or [Ar]
−3
[Ar]
−2
[Ar]
−1
[Ar]
0
[Ar]
+2
+3
15
Formation of
Ionic Compounds
Ionic bonds are formed by the attraction of
cations for anions usually to form solids.
| Commonly, metals react with nonmetals to
form ionic compounds.
| The formation of NaCl is one example of
an ionic compound formation.
|
16
Names and Formulas of
Some Ionic Compounds
|
Formulas of ionic compounds are determined by
the charges of the ions.
z
z
|
|
|
|
Charge on the cations must equal the charge on
the anions.
The compound must be neutral.
NaCl
KOH
CaSO4
Al(OH)3
17
sodium chloride
(Na1+ & Cl1-)
potassium hydroxide(K1+ & OH1-)
calcium sulfate
(Ca2+ & SO42-)
aluminum hydroxide (Al3+ & 3 OH1-)
Formation of
Ionic Compounds
|
Reaction of Group IA Metals with
Group VIIA Nonmetals
IA metal VIIA nonmetal
2 Li(s) + F2(g)
silver
solid
18
yellow
gas
Formation of
Ionic Compounds
|
Reaction of Group IA Metals with
Group VIIA Nonmetals
IA metal VIIA nometal
2 Li (s) + F2(g) → 2 LiF(s)
silver
solid
19
yellow
gas
white solid
o
with an 842 C
melting point
Formation of
Ionic Compounds
|
The underlying reason for the formation of LiF
lies in the electron configurations of Li and F.
1s 2s
2p
Li ↑↓
↑
F ↑↓ ↑↓ ↑↓↑↓↑
These atoms form ions with these configurations.
Li+ ↑↓
F- ↑↓
20
same configuration as [He]
↑↓ ↑↓ ↑↓ ↑↓
same configuration as [Ne]
Formation of
Ionic Compounds
|
We can also use Lewis dot formulas to
represent the neutral atoms and the ions
they form.
Li .
21
+
..
.. .
..F
+
Li
..
.. ..
F
..
[ ]
Octet Rule
The ions want to be like the noble gasses.
| They have same number of electrons as
the noble gas when they make an ion.
| The Li+ ion contains two electrons, same
as the helium atom.
| The F- ion contains ten electrons, same as
the neon atom
|
22
Formation of
Ionic Compounds
|
The reaction of potassium with bromine is
a second example of a group IA metal
with a Group IIA non metal.
IA metal VIIA nonmetal
2 K (s)
+
Br2( z) → 2 KBr (s)
ionic solid
23
Formation of
Ionic Compounds
|
We look at the electronic structures of K and Br.
4s
4p
K [Ar] ↑
Br [Ar] ↑↓ ↑↓ ↑↓ ↑ and the d electrons
The atoms form ions with these electronic structures.
4s
K+
Br-
24
4p
same configuration as [Ar]
↑↓
↑↓ ↑↓ ↑↓
same configuration as [Kr]
Formation of
Ionic Compounds
|
Write the Lewis dot formula representation for the
reaction of K and Br.
You do it!
K.
25
+
..
.. .
Br
..
+
K
..
..Br
..
..
[ ]
Formation of
Ionic Compounds
There is a general trend evident in the
formation of these ions.
| Cations Æ preceding noble gas.
| Anions Æ following noble gas.
|
26
Formation of
Ionic Compounds
Simple Binary Ionic Compounds Table
|
Reacting Groups
IA + VIIA
IIA + VIIA
IIIA + VIIA
IA + VIA
IIA + VIA
IIIA + VIA
27
Compound General Formula
MX
MX2
MX3
M2X
MX
M2X3
Example
NaF
BaCl2
AlF3
Na2O
BaO
Al2S3
Formation of
Ionic Compounds
|
Reacting Groups
Compound General Formula Example
IA + VA
M3X
Na3N
IIA + VA
M3X2
Mg3P2
IIIA + VA
MX
AlN
H, a nonmetal, forms ionic compounds with IA
and IIA metals for example, LiH, KH, CaH2, and
BaH2.
Other hydrogen compounds are covalent.
28
Writing binary chemical formulas
|
Charge becomes subscript. Then give the subscript as
lowest common denominator
Li1+
LiCl
Ca 2+ F −
CaF2
Al 3+ Br −
AlBr3
Mg 2+ O 2−
Mg 2O2 → MgO
Ba 2+
Ba3 N 2
K
+
Cu 2+
29
Cl −
N 3−
Cl
−
I−
Fe3+ O 2−
??
??
??
Naming Some
Inorganic Compounds
|
Binary compounds are made of two
elements.
z
z
|
Name the more metallic element first.
z
|
Use the element’s name.
Name the less metallic element second.
z
30
metal + nonmetal = ionic compound
nonmetal + nonmetal = covalent compound
Add the suffix “ide” to the element’s stem.
Naming Some
Inorganic Compounds
31
Naming Some
Inorganic Compounds
Nonmetal Stems
| Element
| Boron (B)
| Carbon (C)
| Silicon (Si)
| Nitrogen (N)
| Fluorine (F)
| Chlorine (Cl)
|
32
Stem
bor
carb
silic
nitr
fluor
chlor
Naming Some
Inorganic Compounds
Bromine (Br)
| Iodine (I)
| Oxygen (O)
| Sulfur
(S)
| Selenium (Se)
| Phosphorus (P)
| Hydrogen (H)
|
33
brom
iod
ox
sulf
selen
phosph
hydr
Naming Some
Inorganic Compounds
|
Ionic Compounds are made of a metal
cation and a nonmetal anion.
Cation named first
z Anion named second
z
• Stem plus IDE ending
LiBr
| MgCl2
| Li2S
| Al2O3
|
34
lithium bromide
magnesium chloride
lithium sulfide
You do it!
Naming Some
Inorganic Compounds
LiBr
| MgCl2
| Li2S
| Al2O3
| Na3P
|
35
lithium bromide
magnesium chloride
lithium sulfide
aluminum oxide
You do it!
Naming Some
Inorganic Compounds
LiBr
| MgCl2
| Li2S
| Al2O3
| Na3P
| Mg3N2
|
36
lithium bromide
magnesium chloride
lithium sulfide
aluminum oxide
sodium phosphide
You do it!
Naming Some
Inorganic Compounds
LiBr
| MgCl2
| Li2S
| Al2O3
| Na3P
| Mg3N2
|
|
lithium bromide
magnesium chloride
lithium sulfide
aluminum oxide
sodium phosphide
magnesium nitride
Notice that binary ionic compounds with metals
having one oxidation state (representative metals)
do37not use prefixes or Roman numerals.
Naming Some
Inorganic Compounds
|
|
ionic compounds containing
metals that exhibit more than one
oxidation state (charge)—
memorize them, on your handout
Metals exhibiting multiple oxidation
states are:
1.
2.
38
most of the transition metals
metals in groups IIIA (except Al), IVA,
& VA
Naming Some
Inorganic Compounds
|
1.
There are two methods to name these
compounds.
Older method
z
z
2.
Modern method
z
39
add suffix “ic” to element’s Latin name for
higher oxidation state
add suffix “ous” to element’s Latin name
for lower oxidation state
use Roman numerals in parentheses to
indicate metal’s oxidation state
Naming Some
Inorganic Compounds
|
|
|
|
|
|
|
Compound
FeBr2
FeBr3
SnO
SnO2
CoCl2
CoCl3
40
Old System
ferrous bromide
ferric bromide
stannous oxide
stannic oxide
cobaltous chloride
You do it!
Modern System
iron(II) bromide
iron(III) bromide
tin(II) oxide
tin(IV) oxide
cobalt(II) chloride
Naming Some
Inorganic Compounds
|
|
|
|
|
|
|
|
|
Compound
FeBr2
FeBr3
SnO
SnO2
CoCl2
CoCl3
PbS
PbS2
41
Old System
Modern System
ferrous bromide iron(II) bromide
ferric bromide
iron(III) bromide
stannous oxide
tin(II) oxide
stannic oxide
tin(IV) oxide
cobaltous chloride cobalt(II) chloride
cobaltic chloride cobalt(III) chloride
You do it!
You do it!
Naming Some
Inorganic Compounds
|
|
|
|
|
|
|
|
|
Compound
FeBr2
FeBr3
SnO
SnO2
CoCl2
CoCl3
PbS
PbS2
42
Old System
Modern System
ferrous bromide iron(II) bromide
ferric bromide
iron(III) bromide
stannous oxide
tin(II) oxide
stannic oxide
tin(IV) oxide
cobaltous chloride cobalt(II) chloride
cobaltic chloride cobalt(III) chloride
plumbous sulfide lead(II) sulfide
plumbic sulfide
lead(IV) sulfide
Naming Some
Inorganic Compounds
|
There are polyatomic ions that commonly form binary
ionic compounds.
1.
2.
3.
|
|
|
|
|
OH- hydroxide
CN- cyanide
NH4+ ammonium
Use binary ionic compound naming system.
KOH
potassium hydroxide
Ba(OH)2
barium hydroxide
Al(OH)3
aluminum hydroxide
You do it!
Fe(OH)2
43
Naming Some
Inorganic Compounds
|
|
|
|
|
KOH
Ba(OH)2
Al(OH)3
Fe(OH)2
Fe(OH)3
potassium hydroxide
barium hydroxide
aluminum hydroxide
iron (II) hydroxide
You do it!
Formula writing—the polyatomic ion stays
together, if more than one, need
parenthesis
44
Naming Some
Inorganic Compounds
KOH
| Ba(OH)2
| Al(OH)3
| Fe(OH)2
| Fe(OH)3
| Ba(CN)2
|
45
potassium hydroxide
barium hydroxide
aluminum hydroxide
iron (II) hydroxide
iron (III) hydroxide
You do it!
Naming Some
Inorganic Compounds
KOH
| Ba(OH)2
| Al(OH)3
| Fe(OH)2
| Fe(OH)3
| Ba(CN)2
| (NH4)2S
|
46
potassium hydroxide
barium hydroxide
aluminum hydroxide
iron (II) hydroxide
iron (III) hydroxide
barium cyanide
You do it!
Naming Some
Inorganic Compounds
KOH
| Ba(OH)2
| Al(OH)3
| Fe(OH)2
| Fe(OH)3
| Ba(CN)2
| (NH4)2S
| NH4CN
|
47
potassium hydroxide
barium hydroxide
aluminum hydroxide
iron (II) hydroxide
iron (III) hydroxide
barium cyanide
ammonium sulfide
You do it!
Naming Some
Inorganic Compounds
KOH
| Ba(OH)2
| Al(OH)3
| Fe(OH)2
| Fe(OH)3
| Ba(CN)2
| (NH4)2S
| NH4CN
|
48
potassium hydroxide
barium hydroxide
aluminum hydroxide
iron (II) hydroxide
iron (III) hydroxide
barium cyanide
ammonium sulfide
ammonium cyanide
Name or Write the formula:
|
1.
2.
3.
4.
5.
Formula
Cu(OH)2
CuOH
MgCl2
Li2O
Zn3N2
6.
7.
8.
9.
10.
49
Name
calcium bromide
sodium hydroxide
aluminum phosphide
barium iodide
magnesium cyanide
Name or Write the formula:
|
Formula
1.
2.
3.
4.
50
Name
iron(II) bromide
iron(III) hydroxide
copper(II) oxide
lead(IV) cyanide
Naming Some
Inorganic Compounds
Binary Acids are binary compounds
consisting of hydrogen and a
nonmetal.
| Compounds are usually gases at
room temperature and pressure.
|
z
51
Nomenclature for the gaseous
compounds is hydrogen (stem)ide.
Naming Some
Inorganic Compounds
|
|
|
|
|
Formula
HF
HCl
HBr
H2S
52
Name
hydrogen fluoride
hydrogen chloride
hydrogen bromide
You do it!
Naming Some
Inorganic Compounds
|
|
|
|
|
Formula
HF
HCl
HBr
H2S
53
Name
hydrogen fluoride
hydrogen chloride
hydrogen bromide
hydrogen sulfide
Naming Some
Inorganic Compounds
|
Salts of poly atomic ions
z
|
|
|
|
54
–name metal then ion
Salt
NaNO2 sodium nitrite
NaNO3 sodium nitrate
Na2SO3 sodium sulfite
Na2SO4 sodium sulfate
Na3PO4 sodium phosphate
Name these salts
MgSO4
| Ca(NO3)2
| BaCO3
| K3PO4
|
55
Naming Some
Inorganic Compounds
|
Acidic Salts are made from ternary acids
that retain one or more of their acidic
hydrogen atoms.
z
Made from acid base reactions where there is
an insufficient amount of base to react with all
of the hydrogen atoms.
Modern system uses prefixes and the word
hydrogen.
56
Naming Some
Inorganic Compounds
|
NaHCO3
Old system
Modern system
|
KHSO4
Modern system
|
potassium hydrogen sulfate
KH2PO4
Modern system
|
sodium bicarbonate
sodium hydrogen carbonate
K2HPO4
57
potassium dihydrogen phosphate
You do it!
Naming Some
Inorganic Compounds
58
Naming Some
Inorganic Compounds
59
Naming Some
Inorganic Compounds
60