IONIC BONDING

1. JOHNEL V. ESPONILLA
Physical Science Instructor

2. Agenda
The Nature of the Ionic Bond
Ionic Compounds
The Crystal Lattice Structure of Ionic Compounds
Properties of Ionic Compounds

3. THE NATURE OF THE IONIC BOND
 Ionic bonding takes place when the difference in electronegativity
between the two atoms is MORE THAN 1.7.
 This happens when a METAL atom bonds with a NON-METAL atom.
 When the difference in electronegativity is large, one atom will attract the shared
electron pair much more strongly than the other., causing electrons to be
TRANSFERRED from one atom to the other.
METAL NON-METAL
E-NEGATIVITY
> 1.7

4. THE NATURE OF THE IONIC BOND
 IONIC BOND is a type of chemical bond based on the electrostatic
forces between two oppositely charged ions.
 A METAL donates one or more electrons to form a positive ion or cation
and a NON-METAL gains electrons to form a negative ion or anion.
Na Cl
Valence electron:
Na = only one
Cl = seven
Diff. in E-negativity:
2.1
Na+ ion Cl- ion
 A METAL donates one or more electrons to form a positive ion or cation
and a NON-METAL gains electrons to form a negative ion or anion.

5. THE NATURE OF THE IONIC BOND
 The balanced equation for the reaction is:
Na Cl NaCl
 This can be represented using Lewis notation:

6. THE NATURE OF THE IONIC BOND
Mg O
 Ionic bonding takes place between magnesium (Mg) and oxygen (O) to
form magnesium oxide (MgO)
Valence electron:
Mg = ?
O = ?
Diff. in E-negativity:
?

7. THE NATURE OF THE IONIC BOND
 A METAL donates one or more electrons to form a positive ion or cation
and a NON-METAL gains electrons to form a negative ion or anion.
Mg O
Valence electron:
Mg = two
O = six
Diff. in E-negativity:
1.2
Mg2+ ion O2- ion

8. THE NATURE OF THE IONIC BOND
 The balanced equation for the reaction is:
2Mg O2 2MgO
 This can be represented using Lewis notation:

9. CHECKPOINT!!!
Explain the difference between a covalent and an
ionic bond.
 Magnesium and chlorine react to form magnesium chloride.
a. What is the difference in electronegativity between these
two elements?
b. Give the chemical formula for:
oA magnesium ion
oA chloride ion
oThe ionic compound that is produced during this reaction
Allocated Time:
10 minutes

10. CHECKPOINT!!!
Draw Lewis diagram to represent the following
ionic compounds:
a. Sodium iodide (NaI)
b. Calcium bromide (CaBr2)
c. Potassium chloride (KCl)
Allocated Time:
15 minutes

11. THE CRYSTAL LATTICE STRUCTURE
 Ionic substances are actually a combination of lots of ions bonded
together into a giant molecule.
 The arrangement of ions in a REGULAT, GEOMETRIC STRUCTURE is
called CRYSTAL LATTICE.

12. THE CRYSTAL LATTICE STRUCTURE
 The structure of a crystal lattice of NaCl:

13. PROPERTIES OF IONIC COMPOUNDS
 Ions are arranged in a lattice structure
 Ionic solids are crystalline at room temperature
 The ionic bond is a strong electrical attraction
 Ionic compounds are brittle, and bonds are broken along planes when
the compound is stressed.
 Solid crystal don’t conduct electricity, but ionic solutions do.

14. JOHNEL V. ESPONILLA
Physical Science Instructor