Unit 2 Chapter 6 Day 1OBJECTIVE:

Describe how ionic bonds form.Predict the composition of a ionic compound.

• Do Now: • Vocabulary Word Windows-Chapter 6•Today: • Chapter 6 – Atoms and Bonding notes• Practice – Ionic and Covalent Bonds

• Homework:• Everyday Elements•Missing Assignments?

New Chapter New Notebook

Unit 2 Chapter 6 Day 2OBJECTIVE:

Predict the composition of a ionic and covalent compound.

• Do Now: • R & R – Ionic Bonding•Today: • Finish Notes and Practice –

Ionic and Covalent Bonds• Bonding Basics – Ionic and Covalent•Homework:• Read Chapter 6.1 and 6.1 GRWS

Unit 2 Chapter 6 Day 3OBJECTIVE:

Name and Determine chemical formulas for ionic, covalent and molecular compounds.

• Do Now: • Charting Oxidation Numbers•Today: • Homework check and review 6.1 GRWS • Bonding and Chemical Formulas • The Criss-Cross method•Writing and Naming Compounds

• Homework:• Read Chapter 6.2 and 6.2 GRWS

Unit 2 Chapter 6 Day 4 OBJECTIVE:

Model the structure of ionic and covalent molecules.Predict and classify and name ionic and covalent bonds.

• Do Now: • Counting Atoms•Today: • Homework check and review 6.2 GRWS • Continue Writing and Naming Compounds• Bond with a Classmate Activity

• Homework:• Read Chapter 6.3 and 6.3 GRWS

Unit 2 Chapter 6 Day 5 OBJECTIVE:

Model the structure of ionic and covalent molecules.Predict and classify and name ionic and covalent bonds.

•Do Now: •Word Wise Chap 6•Today: •Molecule Models: Model to Formula• Homework check and review 6.3 GRWS •Modeling Molecules Lab• Homework:• Counting Naming Writing Formula review

Unit 2 Chapter 6/7 transitionOBJECTIVE:

Model the structure of ionic and covalent molecules.Predict and classify and name ionic and covalent bonds.

• Star Trek and the Silicon Creature•Modern Marvels Video – Carbon • CSI Online

IONICBONDING

Ionic Bonding” also called “electron transfer

bonding”

Ions are charged atoms

Ions are either “+” (positive)

Or Ions are “-” (negative)

Atoms that undergo ionic bonding either gain or lose electrons

If an atom gains an electron it becomes “-” negatively charged ion

Why? If an atom loses an electron, the overall charge on the ion is

positive.

When 2 ions bond the over all charge on the atom is

NeutralEx: Sodium Fluoride

Na¹+ (more positive)F¹¯ (more negative)YieldsNaF (neutral)

Ion FormationThe process of removing electrons and forming ions is called

IonizationEnergy is needed for ionization

This energy is called

Ionization energy

Ionization energy is

directly related to number of

valence electrons

Less valence electrons= Less ionization energy

EX: Li has 1 valence electron= LOW ionization energy

Other elements with LOW Ionization energiesAlkali metals and Alkaline metals

More valence electrons= HIGH ionization energy

EX: Fluorine has 7 valence

electrons = Very HIGH ionization energy Other elements with HIGH Ionization

energiesHalogens

Why ? It is easier to gain 1

electron then to lose 7

Electron Affinity:•The tendency of an atom

to attract electrons.

Fluorine has a strong electron affinity

Because it only needs one more electron to have a

“full” outer electron shell All Halogens have strong

electron affinities

Why?

Ionic Bonds produce crystal lattice structures

Crystal Lattice structures have repeatable patterns

Lattice structure makes ionic molecule more

stable

Gives physical property of

shapeexample= cubic crystals in salt

Gives a physical property of high melting point

Example:

NaCl (table salt)

One Last word about Ions…• Polyatomic Ions

–A special group of covalently bonded atoms that acts like a single atom

–Example:

OH- (hydroxide)

COVALENT BONDING

Covalent Bonds• (You will need TWO different colored pencils for

today’s lesson)

Covalent Bonding occurs when atoms SHARE electrons.–Usually non metals. –Both of the non metals want to GAIN electrons.

–The elements will SHARE electrons in an effort to fill their outer shells.

METALS

NON-

METALS

Covalent Bonds

• The forces holding covalent molecules together are weaker than ionic bonds –Covalent compounds are often gases or liquids

–They do not conduct electricity–They do not dissolve in water

Covalent Bonds• A good example of a covalent bond is

between two Hydrogen atoms.

H • Hydrogen has one electron in its

electron shell. • Since this shell can have TWO, each

hydrogen will try to gain a second electron.

• A single atom will react with another to form the compound H2

Covalent Bonds• The atoms share each other’s

single electron forming a covalent bond and BOTH atoms have a full electron shell.

H HThis is called a SINGLE covalent

bond

Covalent Bonds

• Draw a single covalent bond for Chlorine:

Cl Cl

Covalent Bonds

• Draw two covalent bonds in water:

H O H

Covalent Bonds• Atoms can share more than one

electron. Oxygen atoms share two electrons to form oxygen molecules:

O O

This is called a DOUBLE covalent bond