Warm up: p201.What is the difference between an

atom and an ion?

Date Session # Activity Page #9/29-30 11 Unknown Substance 18

Physical or Chemical?? 19

10/1-2 12 Bonding Notes 20

Bonding Identification w/s 20

h/w:•Vocab set 2…descriptions•Label bonds:

•Find two substances on a label at home. •Look up the chemical formula•Identify the bonds as ionic or covalent

•Periodic table essay due 10/6

8.P.1 Understand the physical properties of matter and changes that occur when matter interacts in an open or closed container8.P.1.1Classify matter as an element, compound or mixture based on how atoms are packed together in arrangements.8.P.1.3 Compare physical changes such as size, shape and change of state to chemical changes that are a result of a chemical reaction to include changes in temperature, color, gas or formation of a precipitate.

TLW recognize different types of chemical bonds by completing a note sheet, identifying bond properties from demonstrations and completing a bond identification worksheet.

CHEMICAL BONDING

• IONIC BONDS• COVALENT BONDS• METALLIC BONDShttp://ed.ted.com/lessons/how-atoms-bond-george-zaidan-and-charles-morton

What is a chemical bond?

• Attraction between valence electrons of different atoms…form new substances

• Bonding only involves valence electrons

IONIC BONDING

• Transfer of electrons • Occurs between a Metal and a Nonmetal

IONIC BOND FORMATION

Neutral atoms come near each other. Electron(s) are transferred from the Metal atom to the Non-metal atom.

They stick together because of electrostatic forces, like magnets.

IONIC BONDING

IS THE COMPOUND AN IONIC COMPOUND?

METALMETAL NONMETAL

SUBSCRIPTS

IONIC BONDING

Metals will tend to lose electrons and form positive ions

CATIONS

Normal sodium atom loses one electron to become sodium ion

IONIC BONDING

Nonmetals will tend to gain electrons and form negation ions

NEGATIVE ANIONS

Normal chlorine atom gains an electron to become a chloride ion

Properties of Ionic Compounds• Crystalline lattice structure.• High melting points.• Conduct electricity when

dissolved in water.

Ex: NaCl (table salt)

COVALENT BONDING

• Share valence electrons

• Occur between nonmetals

COVALENT BONDING

IS THE COMPOUND A COVALENT COMPOUND?

NONMETALNONMETAL NONMETAL

YES since it is made of only nonmetal elementsYES since it is made of only nonmetal elements

Covalent bonding

• Fluorine has seven valence electrons

F

Covalent bonding

• Fluorine has seven valence electrons• A second atom also has seven

F F

Covalent bonding Fluorine has seven valence electrons A second atom also has seven By sharing electrons

F F

Covalent bonding Fluorine has seven valence electrons A second atom also has seven By sharing electrons

F F

Covalent bonding Fluorine has seven valence electrons A second atom also has seven By sharing electrons

F F

Covalent bonding Fluorine has seven valence electrons A second atom also has seven By sharing electrons

F F

Covalent bonding Fluorine has seven valence electrons A second atom also has seven By sharing electrons

F F

Covalent bonding Fluorine has seven valence electrons A second atom also has seven By sharing electrons Both end with full orbitals

F F

Covalent bonding Fluorine has seven valence electrons A second atom also has seven By sharing electrons Both end with full orbitals

F F8 Valence electrons

Covalent bonding Fluorine has seven valence electrons A second atom also has seven By sharing electrons Both end with full orbitals

F F8 Valence electrons

Polar Covalent Bonds• UNEQUAL sharing of valence electrons.

• Ex: H2O

Adhesion, cohesion, capillary action, surface tension….

Covalent Bond Properties

• Create MOLECULES• Poor conductors of electricity• Low melting points

Metallic Bonds• Occur between metals• Metals have a weak hold onto their

valence electrons.• Metal nuclei “float” in a “sea of

electrons.”

Metallic Bond Properties• Electrons are free to move through the

solid.• Metals conduct electricity.

+ + + ++ + + +

+ + + +

Why do atoms bond???Octet Rule states that elements gain or lose electrons to create the valence electron arrangement (configuration) of the nearest noble gas. THEY NEED 8 VALENCE ELECTRONS TO BE STABLE

Oct prefix means: “8”