1. Ionic Bonding and Ionic CompoundsBy
Doba Jackson, Ph.D.

2. Molecules, Ions, and Chemical Bonds
Covalent Bond: A bond that results from the sharing of electrons between atoms.

3. Molecules, Ions, and Chemical Bonds

4. Definitions of Molecules, Ions, and Chemical Bonds
Ionic Bond: A transfer of one or more electrons from one atom to another. An electrostatic attraction between charged particles. Typically a metal bonded to a nonmetal.
Ion: A charged particle.
Cation: A positively charged particle. Metals tend to form cations.
Anion: A negatively charged particle. Nonmetals tend to form anions.

5. Ions, and Chemical Bonds
In the formation of sodium chloride, one electron is transferred from the sodium atom to a chlorine atom.
11 protons
11 electrons
17 protons
17 electrons 1 2
Na Cl1-
Na Cl2
11 protons
10 electrons
17 protons
18 electrons

7. Electron Configurations of Ions
Atoms
Ions
- e-
Na:
Cl:
1s2 2s2 2p6 3s1
1s2 2s2 2p6 3s1 3p5
Na1+:
Cl1-:
1s2 2s2 2p6
1s2 2s2 2p6 3s1 3p6
+ e-

9. Electron Configurations of Ions
Atoms
Ions
-2 e-
Fe:
[Ar] 4s2 3d6
Fe+2:
Fe+3:
[Ar] 3d6
[Ar] 3d5
-3 e-

10. Ionic Radii

11. Ionic Radii of Anions

12. Ionization Energy
Ionization Energy (Ei): The amount of energy necessary to remove the highest-energy electron from an isolated neutral atom in the gaseous state.

13. Ionization Energy

14. Ionization Energy Boron has a lower Ei due to a smaller Zeff
(shielding by the 2s electrons)

15. Higher Ionization Energy
M1+ + e-
M + energy
M2+ + e-
M1+ + energy
M3+ + e-
M2+ + energy

16. Electron Affinity
Electron Affinity (Eea): The energy released when a neutral atom gains an electron to form an anion.
Books use different conventions. The one this book uses assigns a negative sign to electron affinity.

17. The Octet Rule
Octet Rule: Main-group elements tend to undergo reactions that leave them with eight outer-shell electrons.

18. The Octet Rule 1) Metals tend to have low Ei and low Eea.
Octet Rule: Main-group elements tend to undergo reactions that leave them with eight outer-shell electrons.
1) Metals tend to have low Ei and low Eea.
They tend to lose one or more electrons.
2) Nonmetals tend to have high Ei and high Eea.
They tend to gain one or more electrons.

19. Problem 1: Predict the charge on a Calcium ion
Ca: [Ar] 4s2
Ca+2: [Ar]
Ca+2

20. Evidence for existence of ions

21. How can we predict the ionic charges of d-block and larger p-block metals?

22. Lets focus on Silver (Ag)
Electron configuration of Ag
(Ideal based on periodic table) Ag: [Kr] 5s2 4d9
(Actual: based on experiments) Ag: [Kr] 5s1 4d10
Silver needs one electron to fill its d-orbital which
will complete its 4-th shell. It will then steal an electron from
the 5s orbital to complete the 4d and leave the 5s unpaired.
-1 e-
Ag: [Kr] 5s1 4d10
Ag+1: [Kr] 4d10
18 electron rule
[N.G.] nd10

23. Other metal ions that have the 18 outer electron configuration
[N.G.] nd10

24. Lets focus on Lead (Pb) which is found in two ionic forms (Pb+2, Pb+4)
Electron configuration of Pb
(Actual/Ideal) Pb: [Xe] 6s2 5d10 6p2
Lead can lose 4 e- to achieve the 18 electron rule
-4 e-
Pb: [Xe] 6s2 5d10 6p2
Pb+4: [Xe] 5d10
Lead can lose 2 e- in its partially filled p-orbital
-2 e-
Pb: [Xe] 6s2 5d10 6p2
Pb+2: [Xe] 6s2 5d10
Stable ions: Pb+2, Pb+4

25. Common metal ions with configurations of [N.G.] ns2 (n-1) d10

26. Many elements have multiple stable ionic forms

27. Naming Ionic Compounds
Chapter 4: Ionic Bonds and Some Main-Group Chemistry
7/20/2018
Naming Ionic Compounds +1 +2
Naming (IUPAC) -3 -2 -1 +3
Cation Anion
Na Cl-1
Sodium Chloride
Metals tend to form Cations
Nonmetals tend to form Anions
Copyright © 2010 Pearson Prentice Hall, Inc.

28. Naming Ionic Compounds
Chapter 4: Ionic Bonds and Some Main-Group Chemistry
7/20/2018
Naming Ionic Compounds
Ionic Compound: A neutral compound in which the total number of positive charges must equal the total number of negative charges.
Some binary Ionic Compounds
Cation – Anion(ide)
Cation
Anion
Ionic Compound
cation anion(ide)
C+x
A-y
CyAx
sodium chloride
NaCl
Na+1
Cl-1
magnesium oxide
MgO
Mg+2
O-2
aluminum sulfide:
Al2S3
Al+3
S-2
Copyright © 2010 Pearson Prentice Hall, Inc.

29. What happens when the cation has more than one oxidation state
Chapter 4: Ionic Bonds and Some Main-Group Chemistry
7/20/2018
What happens when the cation has more than one oxidation state
Use Roman numerals in parentheses to indicate the charge on metals that form more than one kind of cation.
Some binary Ionic Compounds
Cation Anion(ide)
Cation
Anion
Ionic Compound
cation (x) anion(ide)
C+x
A-y
CyAx
iron (III) oxide
Fe2O3
Fe+3
O-2
tin (II) chloride
SnCl2
Sn+2
Cl-1
lead (II) flouride
PbF2
Pb+2
F-1
Copyright © 2010 Pearson Prentice Hall, Inc.

31. Determine the charge on each compound and name the compound
MgS
BaF2
AlP
Ga2O3
Li2O
Mg3N2
CaS
Fe+3
O-2
Pb+4
Ni+2
Br-1
Manganese (IV) Oxide
Tungsten (VI) bromide
Mg+2
S-2
Magnesium sulfide
Ba+2
F-1
Barium flouride
Al+3
P-3
Aluminum Phosphide
Ga+3
O-2
Gallium oxide
O-2
Lithium oxide
Li+1
Mg+2
N-3
Magnesium nitride
Ca+2
S-2
Calcium sulfide
Fe2O3
Iron (III) oxide
PbO2
Lead (IV) oxide
NiBr2
Nickel Bromide
MnO2
Mn+4
O-2
Br-1
WBr6
W+6