1. Introduction to Chemical Bonding
Ions and Ionic Compounds

2. Chemical Compounds Types of chemical compounds Ionic compounds
Molecular compounds or covalent compounds

3. Ionic compounds What are Ionic compounds?
Ionic compounds are chemical compounds composed of cations (metals) and Anions (nonmetals)
Usually are solid crystals at room temperature
High density, High melting and boiling point
Formed by ionic bonds (atoms gain or lose e-)
NaCl

4. Ionic Compounds
The representative unit of Ionic compounds
Ionic compounds conduct electricity when dissolved in water
The representative unit of the ionic compounds are the formula unit (a balance of opposite charged ions)

5. Representing and Naming Ions
Cations
Positive Ion
Produced when one or more electrons are lost from a neutral atom.
Mg Mg e-
Al Al e-

6. Representing and Naming Ions
Cations
A cation is named using the name of the parent atom.
Na+ = Sodium ion
Mg2+ = Magnesium ion
Al3+ = Aluminum ion

7. Representing and Naming Ions
Anions
Negative ion
Produced when an atom gains one or more electrons.
Cl + e Cl-
O + 2e O2-

8. Representing and Naming Ions
Anions
An anion is named by taking the root name of the atom and changing the ending by adding the suffix –ide
Atom
Anion
Fluorine
Fluoride
Oxygen
Oxide
Sulfur
Sulfide

9. Writing formulas for ionic compounds
There must be both positive ions (cations) and negative ions (anions) present.
The numbers of cations and anions must be such that the net charge is zero.

10. Writing formulas for ionic compounds
Na+ + Cl NaCl
charge charge net charge =
Mg MgCl2
charge anion charge net charge
x (-1) =
Cl-
Cl-

11. Naming Compounds that Contain a Metal and a Nonmetal
Binary Ionic Compounds
Binary ionic compounds contain a cation, which is always written first in the formula, and an anion.
To name these compounds we simply name the ions.

12. Types of ionic compounds
Type I ionic compounds
They are binary compounds (two elements present only)
The metal present cations with only one charge.
All the alkali metals (+1), the alkaline earth metals (+2), Ag+1 , Zn+2 , Cd+2 , Al+3 , H+ .
When naming the compound, name metal first, then the anion with –ide ending.

13. Types of Ionic compounds
They are binary compounds (two elements only)
The metals present cations with several charges.
When naming the compound we must use Roman Numerals to indicate the charge of the cation. The anion is named the same way as the type I compounds
The transition metals and metals next to metalloids usually make cations with several charges.
Type II ionic compounds

14. Types of Ionic Compounds
Type III Ionic compounds
It uses any metal with polyatomic anion
A polyatomic ion is an anion that has more than one element. Usually it has an oxygen.
The name of the polyatomic ion has two possible endings -ate or –ite
It depends on the number of oxygens it has.

15. Ionic compounds graphic organizer
when dissolved in water
__State at room Temp.
______ _Example__
Ionic compounds
__Composed of__
___Representative unit
____It has a high_

16. Molecular compounds What are molecular compounds? What is a molecule?
Compounds composed of molecules.
AKA covalent compounds.
It is the smallest electrically neutral unit of a substance that still has the properties of the substance.

17. Molecular Compounds Molecules
Molecules are made of two or more atoms that act as a unit.
The molecules of most molecular compounds are composed of the atoms of two or more nonmetals.
Example: H2O

18. Molecular Compounds
Most molecular compounds tend to exist as gases or liquids at room temperature. There are, also, a few solid molecular compounds.
Molecular compounds tend to have:
Low melting and boiling points
Low density
Formed by covalent bonds (atoms sharing electrons)
Molecular compounds

19. Naming Molecular Compounds
Molecular compounds do not conduct electricity when dissolved in water.
Molecular compounds are nonmetals with nonmetals.
They are formed by covalent bonds.
To name molecular compounds, we must use prefixes.
Molecular compounds

20. Naming Molecular Compounds
Prefixes
Number
Mono 1 Di 2
Tri 3
Tetra 4
Penta 5
Hexa 6
Hepta 7
Octa 8
Nona 9
Deca 10
Prefixes used to name binary molecular compounds.

21. Molecular compounds graphic organizer
when dissolved in water __
__State at room Temp.
______ _ Example__
Molecular compounds
_ Composed of__
___Representative unit
____It has a low__ 21