Intro to Bonding:Ionic Compounds(Type 1 and 2 Binary Compounds)

What is a bond?

• A bond is a force that holds groups of two or more atoms together.

• For Example:– Water (H2O)• A water molecule is held

together by two bonds:a bond between bothH-O

Types of bonds• There are 3 types of bonds that we are going

to focus on:

1. Ionic Bonds

2. Covalent Bonds• Polar• Nonpolar

3. Metallic Bonds

Ionic Bonds

• A strong bonding force resulting from the attraction of oppositely charged ions.

• Ionic compounds result when a metal reacts with a nonmetal.

• An ionic compound contains a cation (metal) and an anion (nonmetal).

• Example:– Sodium chloride (NaCl)• Sodium (Na+) is the cation (metal)• Chloride (Cl-) is the anion (nonmetal)

Ionic Bonds • The metal loses an electron

to form a cation.• The nonmetal gains that

electron from that metal toform an anion.

• The result is an ionic bond and the formation of an ioniccompound.

• The ionic bond is an attraction between ions.

Ionic Bonds - Cations

• If we look at the periodic table, the metals are colored in green. The metals lose electrons to form positively charged cations.

Ionic Bonds - Cations• Cation charge can be determined by looking at

how the periodic table is organized.• The alkali metals have a +1 charged cation

because they donate 1 electron.• The alkaline earth metals have a +2 charged

cation because they donate 2 electrons.• Metals in column 13

have a +3 charged cation because theydonate 3 electrons.

+1 +2 +3 Transition metals have multiple charges

Ionic Bonds - Transition Metal Cations

• Transition Metals have multiple charges• For example:– Lead can be Pb+2 or Pb+4

– Copper can be Cu+1 or Cu+2

– Gold can be Au+1 or Au+3

– Iron can be Fe+2 or Fe+3

– and the list goes on…+1 +2 +3 Transition metals have multiple charges

Ionic Bonds – Anions

• If we look at the periodic table, the nonmetals are colored in purple. The nonmetals gain electrons to formnegatively charged anions.

Ionic Bonds - Anions• Anion charge can be determined by looking at

how the periodic table is organized.• The halogens have a -1 charged anion because

they are able to accept 1 electron.• Nonmetals in column 16 have a -2 charged

anion because they are able to accept 2 electrons.

• Nonmetals in column 15 have a -3 charged anion because theyare able to accept 3 electrons.

-3 -2 -1