Starter S-53

Mole Day!

Mole Day!

Starter S-55

What is the value of a mole?

What is that number used for?

Ionic and Metallic Bonding

Chapter 7

7.1 Ions

Chapter 7

Valence Electrons – highest energy electrons

Groups always have the same number of valence electrons

7.1 Ions

Valence electrons are related to the group

Valence electrons are usually the ones involved in chemical bonding

7.1 Ions

Octet Rule

Metals tend to lose their valence electrons leaving a complete octet in the next lowest energy level

Nonmetals tend to gain or share electrons to complete their octet

7.1 Ions

Ionic Bonding

Ionic Bonding involves the formation of a

Cation – lose electrons

Anions – gain electrons

7.1 Ions

Formation of Ions

Electron configuration change in cation formation

7.1 Ions

Al

3s 3p 3d

2s 2p

1s

Al+3

Lower Octet

Electron configuration change in anion formation

7.1 Ions

S

3s 3p 3d

2s 2p

1s

S-2

New Octet

Oxidation Number – apparent charge in a compound

7.1 Ions

Starter S-57

What is an ion?

How many electrons does Oxygen need in its outer energy level to be stable?

Why does Helium only need two electrons to be stable?

7.2 Ionic Bonds and Ionic Compounds

Chapter 7

Ionic Compounds – composed of cations and anions

One element give electrons to the other element

7.2 Ionic Bonds and Ionic Compounds

Writing formulas for ionic compounds

The sum of the charges always equals 0

Usually if we flip the

number values

So the formula would be

7.2 Ionic Bonds and Ionic Compounds

2 1 1

2 1 1 0

Ca Cl Cl

2CaCl

Positive ion is always written first

Numbers are written after the element and as a subscript

The number 1 is never written

7.2 Ionic Bonds and Ionic Compounds

Try Aluminum and Oxygen

Calculations

Formula

7.2 Ionic Bonds and Ionic Compounds

3 3 2 2 2

3 3 2 2 2 0

Al Al O O O

2 3Al O

Formulas are always given as smallest ratio so

Calculations

Formula

7.2 Ionic Bonds and Ionic Compounds

4 4 2 2 2 2

4 4 2 2 2 2 0

Pb Pb O O O O

2 4Pb O

Pb+4 O-2

2PbO

Formula Unit – the smallest whole number ratio of ions

Ionic Compounds are

really repeating structures

7.2 Ionic Bonds and Ionic Compounds

Properties of Ionic Compounds

1. Most are crystalline solids at room temperature

2. Generally have high melting points

3. Conduct an electric current when melted or dissolved

7.2 Ionic Bonds and Ionic Compounds

Starter S-59

What is the formula for

1. Vanadium (VI) and Oxygen

2. Vanadium (V) and Oxygen

3. Lead (IV) and Sulfur

4. Lead (II) and Sulfur

7.3 Bonding in Metals

Chapter 7

In metals valence electrons are free to move around

The individual atoms are free to slide past each other

Explains conductivity – electrons are free to move

7.3 Bonding in Metals

Bonding Animation

Ductility and Malleability – metals free to slide past each other

Metals are arranged in compact and orderly crystal patterns

Body Centered Cubic-every atom has eight neighbors

Na, K, Fe, Cr, W

7.3 Bonding in Metals

Crystal Structures

Face Centered Cubic – every atom has 12 neighbors

Cu, Ag, Au, Al,

Pb

Hexagonal Close Packed – 12 different pattern

Mg, Zn, Cd

7.3 Bonding in Metals

Alloys – mixtures composed two or more elements, at least one of which is a metal

Sterling silver

92.5% silver, 7.5% copper

Harder, more durable than Ag

Bronze

87.5% copper, 12.5% tin

Harder, more easily cast

7.3 Bonding in Metals

Steel

Stainless Steel (80.6% Fe, 18.0% Cr, 0.4% C, 1.0 % Ni)

Spring Steel (98.6% Fe, 1.0% Cr,

0.4% C)

7.3 Bonding in Metals

Surgical Steel (67% Fe, 18% Cr, 12% Ni, 3% Mo)

7.3 Bonding in Metals

Starter S-60

What is the chemical formula of

A. Iron (III) and Chlorine

B. Calcium and Fluorine

C. Sodium and Oxygen