review: what do we already know? protons determine the identinty of the element valance electrons...

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REVIEW: WHAT DO WE ALREADY KNOW?

• PROTONS DETERMINE THE IDENTINTY OF THE ELEMENT

• VALANCE ELECTRONS DETERMINE THE CHEMICAL PROPERTIES OF AN ELEMENT.

• VALANCE ELECTRONS ARE THE ELECTRONS IN THE OUTER ENERGY LEVEL

• FOR REPRESENTATIVE ELEMENTS LOOK AT THE GROUP NUMBER TO DETERMINE THE NUMBER OF VALANCE ELECTRONS

• ELEMENTS LOSE OR GAIN ELECTRONS TO ACHIEVE A FULL OUTER ENERGY LEVEL (FULL OCTET)

• METALS FORM CATIONS BY LOSING ELECTRONS

• NONMETALS FORM ANIONS BY GAINING ELECTRONS

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REVIEW:THE OCTET RULE

• OCTET RULE STATED THAT IN FORMING COMPOUNDS ATOMS TEND TO ACHIEVE THE ELECTRON CONFIGURATION OF A NOBLE GAS.

• AN OCTET IS A SET OF EIGHT ELECTRONS

• ATOMS OF METALS TEND TO LOSE THEIR VALENCE ELECTRONS LEAVING A COMPLETE OCTET IN THE NEXT-LOWEST ENERGY LEVEL.

• ATOMS OF SOME NONMETALS TEND TO GAIN ELECTRONS OR TO SHARE ELECTRONS WITH ANOTHER NONMETALS TO ACHIEVE A COMPLETE OCTET.

• WHAT IS A COMPOUND?

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BONDINGCHEMISTRY CHAPTER 5 & 6

I. INTRODUCTION TO BONDING

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BONDING:A. VOCABULARY

• CHEMICAL BOND

• ATTRACTIVE FORCE BETWEEN ATOMS OR IONS THAT BINDS THEM TOGETHER AS A UNIT

• BONDS FORM IN ORDER TO…

• DECREASE POTENTIAL ENERGY (PE)

• INCREASE STABILITY

IONIC COVALENTBond Formation

Type of Structure

Solubility in Water

Electrical Conductivity

OtherProperties

e- are transferred from metal to nonmetal

high

yes (solution or liquid)

yes

e- are shared between two nonmetals

low

no

usually not

MeltingPoint

crystal lattice true molecules

B. TYPES OF BONDS

Physical State solid liquid or gas

odorous

“electron sea”

METALLICBond Formation

Type of Structure

Solubility in Water

Electrical Conductivity

OtherProperties

MeltingPoint

B. TYPES OF BONDS

Physical State

e- are delocalized among metal atoms

very high

yes (any form)

no

malleable, ductile, lustrous

solid

C. BOND POLARITY

• MOST BONDS ARE A BLEND OF IONIC AND COVALENT CHARACTERISTICS.

• DIFFERENCE IN ELECTRONEGATIVITY DETERMINES BOND TYPE.

C. BOND POLARITY

• ELECTRONEGATIVITY

• ATTRACTION AN ATOM HAS FOR A SHARED PAIR OF ELECTRONS.

• HIGHER E-NEG ATOM -

• LOWER E-NEG ATOM +

C. BOND POLARITY

• ELECTRONEGATIVITY TREND (P. 151)

• INCREASES UP AND TO THE RIGHT.

• NONPOLAR COVALENT BOND

• E- ARE SHARED EQUALLY

• SYMMETRICAL E- DENSITY

• USUALLY IDENTICAL ATOMS

C. BOND POLARITY

+ -

C. BOND POLARITY

• POLAR COVALENT BOND

• E- ARE SHARED UNEQUALLY

• ASYMMETRICAL E- DENSITY

• RESULTS IN PARTIAL CHARGES (DIPOLE)

Nonpolar

Polar

Ionic

View Bonding Animations.

C. BOND POLARITY

http://207.10.97.102/chemzone/lessons/03bonding/dogbonds.htm

C. BOND POLARITY

EXAMPLES:

• CL2

• HCL

• NACL

3.0-3.0=0.0Nonpolar

3.0-2.1=0.9Polar

3.0-0.9=2.1Ionic

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II. IONIC BONDING AND NAMING

CHAPTER 7 AND 9

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• SC1 STUDENTS WILL ANALYZE THE NATURE OF MATTER AND ITS CLASSIFICATIONS.

• SC1.B. IDENTIFY SUBSTANCES BASED ON CHEMICAL AND PHYSICAL PROPERTIES.

• SC1.C. PREDICT FORMULAS FOR STABLE IONIC COMPOUNDS (BINARY AND TERTIARY) BASED ON BALANCE OF CHARGES.

• SC1.D. USE IUPAC NOMENCLATURE FOR BOTH CHEMICAL NAMES AND FORMULAS:

• SC1.D.1 IONIC COMPOUNDS (BINARY AND TERTIARY)

• SC1.D.3 ACIDIC COMPOUNDS (BINARY AND TERTIARY)

• SC3.E. COMPARE AND CONTRAST TYPES OF CHEMICAL BONDS (I.E. IONIC, COVALENT).

• SC3.B. USE THE ORBITAL CONFIGURATION OF NEUTRAL ATOMS TO EXPLAIN ITS EFFECT ON THE ATOM’S CHEMICAL PROPERTIES.

IONIC BONDING AND NAMINGA. IONIC NOMENCLATURE

COMMON ION CHARGES

1+

2+ 3+NA 3- 2- 1-

0

IONIC BONDING AND NAMINGA. VOCABULARY

ION

PolyatomicIon

MonatomicIon

1 atom 2 or more atoms

NO3-Na+

IONIC BONDING AND NAMINGA. VOCABULARY

COMPOUND

TernaryCompound

BinaryCompound

2 elementsmore than 2

elements

NaNO3NaCl

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IONIC BONDING AND NAMINGFORMATION OF IONIC COMPOUNDS

• IONIC COMPOUNDS ARE COMPOUNDS COMPOSED OF CATIONS AND ANIONS.

• ALTHOUGH THEY ARE COMPOUNDS OF IONS, IONIC COMPOUNDS ARE ELECTRICALLY NEUTRAL.

• IONIC BONDS ARE THE ELECTROSTATIC FORCES THAT HOLD IONS TOGETHER IN IONIC COMPOUNDS. THEY OCCUR DUE TO THE TRANSFER OF ELECTRONS

• CHEMICAL FORMULA SHOWS THE KINDS AND NUMBERS OF ATOMS IN THE SMALLEST REPRESENTATIVE UNIT OF A SUBSTANCE.

• FORMULA UNIT IS THE LOWEST WHOLE-NUMBER RATIO OF IONS IN AN IONIC COMPOUND

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IONIC BONDING AND NAMINGB. LEWIS STRUCTURE

• ELECTRON DOT STRUCTURES (LEWIS DOT STRUCTURE) ARE DIAGRAM THAT SHOW THE VALENCE ELECTRONS AT DOTS.

• EACH VALANCE ELECTRON IS REPRESENTED WITH A DOT

• PUT ONE DOT ON EACH SIDE OF THE SYMBOL BEFORE PUTTING TWO ON ONE SIDE.

• EXAMPLES

1.Carbon2.Calciu

m3.Chlorin

e4.Argon

4 valance e-2 valance e-7 valance e-8 valance e-

CCa

ClAr

IONIC BONDING AND NAMINGB. LEWIS STRUCTURES

• IONIC – SHOW TRANSFER OF E-

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IONIC BONDING AND NAMINGD. FORMULA WRITING

1. WHEN WRITING FORMULAS THE MOST METALIC ELEMENT IS WRITTEN FIRST

• IONIC BONDS OCCUR BETWEEN METALS AND NONMETALS SO THE METAL IS ALWAYS WRITTEN FIRST.

2. DETERMINE THE ION THAT THE ELEMENTS WILL FORM

3. BALANCE CHARGES

• CAN SWITCH CHARGES AND REDUCE IF NECESSARY

• OVERALL CHARGE MUST EQUAL ZERO.

• IF CHARGES CANCEL, JUST WRITE SYMBOLS.

• IF NOT, USE SUBSCRIPTS TO BALANCE CHARGES.

• USE PARENTHESES TO SHOW MORE THAN ONE POLYATOMIC ION.

• STOCK SYSTEM - ROMAN NUMERALS INDICATE THE ION’S CHARGE.

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• PRACTICE 1: OXYGEN AND SODIUM

1. SODIUM IS METAL SO IT MUST BE WRITTEN FIRST

2. NA FORMS +1 ION AND O FORMS -2 ION

3. NA+1 O-2 SWITCHING CHARGES GIVES NA2O

(# METAL) +1 +(#NONMETAL) -2 = 0 SOLVE

(2) +1 +(1) -2 = 0 GIVES NA2O

NOTE: THE SUBSCRIPT OF 1 IS NOT WRITTEN

• PRACTICE 2: NITROGEN AND ALUMINUM

1. ALUMINUM IS METAL SO IT MUST BE WRITTEN FIRST

2. AL FORMS +3 ION AND N FORMS -3 ION

3. AL+3 N-3 SWITCHING CHARGES GIVES ALN (MUST REDUCE)


(1) +3 +(1) -3 = 0 GIVES ALN

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• PRACTICE 3: CALCIUM AND CARBON

1. CALCIUM IS METAL SO IT MUST BE WRITTEN FIRST

2. CA FORMS +2 ION AND C FORMS -4 ION

3. CA+2 C-4 SWITCHING CHARGES GIVES CA2C


(2) +2 +(1) -4 = 0 GIVES CA2C

• PRACTICE 4: BARIUM AND PHOSPHATE (PO4-3)

1. BARIUM IS METAL SO IT MUST BE WRITTEN FIRST

2. BA FORMS +2 ION AND PO4 IS A -3 ION

3. AL+2 PO4-3 SWITCHING CHARGES GIVES AL3(PO4)2


(3) +2 +(2) -3 = 0 GIVES AL3(PO4)2

MUST USE PARENTHESIS TO SHOW HAVING 2 PHOSPHATE MOLECULES.

IONIC BONDING AND NAMINGE. IONIC NOMENCLATURE

IONIC NAMES

• WRITE THE NAMES OF BOTH IONS, CATION FIRST.

• CHANGE ENDING OF MONATOMIC IONS TO -IDE.

• POLYATOMIC IONS HAVE SPECIAL NAMES.

• STOCK SYSTEM - USE ROMAN NUMERALS TO SHOW THE ION’S CHARGE IF MORE THAN ONE IS POSSIBLE. OVERALL CHARGE MUST EQUAL ZERO.


• CONSIDER THE FOLLOWING:

• DOES IT CONTAIN A POLYATOMIC ION?

• -IDE, 2 ELEMENTS NO

• -ATE, -ITE, 3+ ELEMENTS YES

• DOES IT CONTAIN A ROMAN NUMERAL?

• CHECK THE TABLE FOR METALS NOT IN GROUPS 1 OR 2.

• NO PREFIXES!


COMMON ION CHARGES

1+

2+ 3+NA 3- 2- 1-

0

potassium chloride

magnesium nitrate

copper(II) chloride

K+ Cl-

Mg2+ NO3-

Cu2+ Cl-

KCl

Mg(NO3)2

CuCl2


NaBr

Na2CO3

FeCl3

sodium bromide

sodium carbonate

iron(III) chloride


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IONIC NAMING – TYPE 1 METALS

TYPE 1 METALS ARE METALS THAT FORM ONLY 1 OXIDATION STATE.

THEY ARE FOUND IN GROUPS 1, 2, & 13 IN ADDITION TO ZN+2, CD+2, AND AG+1

1. DETERMINE THE CATION AND THE ANION

2. IF THE CATION IS FROM A REPRESENTATIVE ELEMENT WRITE ITS NAME

3. THE ANION IS:

a. POLYATOMIC ION WRITE IT’S SPECIAL NAME

b. SINGLE NONMETAL ELEMENT WRITE ITS ROOT NAME FOLLOWED BY “IDE”

4. WRITE BOTH PARTS OF NAME SIDE BY SIDE

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IONIC NAMING – TYPE 1

• EXAMPLE 1: CA3N2

1. CALCIUM IS THE CATION, NITROGEN IS ANION

2. CALCIUM STAYS CALCIUM

3. NITROGEN IS NOT A POLYATOMIC SO IT BECOMES NITRIDE

4. CA3N2 IS CALLED CALCIUM NITRIDE

• EXAMPLE 1: CA3(PO4)2

1. CALCIUM IS THE CATION, PHOSPHATE IS ANION

2. CALCIUM STAYS CALCIUM

3. PHOSPHATE IS A POLYATOMIC SO IT’S NAME IS PHOSPHATE

4. CA3(PO4)2 IS CALLED CALCIUM PHOSPHATE

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1. KCL

2. ALCL3

3. CA2C

4. INN

5. RB3PO3

6. AL(OH)3

7. IN2(SO3)3

8. (NH4)3BR

1. Potassium chloride2. Aluminum chloride3. Calcium carbide4. Indium nitride5. Rubidium phosphite6. Aluminum hydroxide7. Indium sulfite8. ** Ammonium bromide

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• MOST TRANSITION METALS HAVE THE ABILITY TO BORROW ELECTRONS FROM OTHER ORBITALS AND CAN FORM IONS WITH DIFFERENT CHARGES.

• METALS IN GROUP 14 ALSO HAVE MULTIPLE OXIDATION STATES. +2 OR +4

• EXAMPLE: IRON CAN FROM A +3 OR +4 CATION, COPPER CAN FROM A +2 OR +1 ION

• NOT ALL TRANSITION METAL DO THIS BUT MOST DO SO WHEN WE NAME THE COMPOUND WE HAVE TO STATE THE CHARGE OF THE METAL ION

• EXCEPTIONS: THREE TRANSITION METALS THAT YOU MUST MEMORIZE THE FOLLOWING: ZN+2, CD+2, AG+1 AS THEY DO NOT NEED ROMAN NUMERALS

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1. DETERMINE THE CATION AND THE ANION

2. IF THE CATION IS FROM A TRANSITION ELEMENT WRITE ITS NAME FOLLOWED BY A ROMAN NUMERAL TO SHOW THE CHARGE OF THE METAL ION.

3. THE ANION IS A:

a. POLYATOMIC ION WRITE IT’S SPECIAL NAME

b. SINGLE NONMETAL ELEMENT WRITE ITS ROOT NAME FOLLOWED BY “IDE”

4. WRITE BOTH PARTS OF NAME SIDE BY SIDE

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• COMMON ROMAN NUMERALS YOU MUST KNOW

1. I 6. VI **

2. II 7. VII

3. III 8. VIII

4. IV ** 9. IX

5. V 10. X

** COMMONLY CONFUSED BY STUDENTS

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• EXAMPLE 1: FEO

1. FE IS CATION AND O IS ANION

2. SINCE OXYGEN HAS A -2 CHARGE FE MUST HAVE A +2 SO IT IS IRON (II)

3. O IS NOT A POLYATOMIC SO IT BECOMES OXIDE

4. FEO IS IRON (II) OXIDE

• EXAMPLE 2: FE2O3

1. FE IS CATION AND O IS ANION

2. SINCE OXYGEN HAS A -2 CHARGE FE MUST HAVE A +3 SO IT IS IRON (III)


4. FEO IS IRON (III) OXIDE

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• EXAMPLE 3: FEPO4

1. FE IS CATION AND PO4 IS ANION

2. SINCE PO4 HAS A -3 CHARGE FE MUST HAVE A +3 SO IT IS IRON

(III)

3. PO4 IS A POLYATOMIC SO IT IS PHOSPHATE

4. FEO IS IRON (III) PHOSPHATE

• EXAMPLE 4: AG2O

1. AG IS CATION AND O IS ANION

2. AG IS AN EXCEPTION AND ONLY FORMS A +1 ION SO IS SILVER


4. AG2O IS SLIVER OXIDE

REMEMBER ZN+2, CD+2, AG+1 DO NOT NEED ROMAN NUMERALS

C. IONIC NOMENCLATUREIONIC FORMULAS

• WRITE EACH ION, CATION FIRST. DON’T SHOW CHARGES IN THE FINAL FORMULA.

• OVERALL CHARGE MUST EQUAL ZERO.• IF CHARGES CANCEL, JUST WRITE SYMBOLS.• IF NOT, USE SUBSCRIPTS TO BALANCE CHARGES.

• USE PARENTHESES TO SHOW MORE THAN ONE POLYATOMIC ION.

• STOCK SYSTEM - ROMAN NUMERALS INDICATE THE ION’S CHARGE.

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IONIC NAMES TO FORMULA

1. USE THE NAME TO DETERMINE THE IONS OF THE ELEMENTS (OR POLYATOMIC) IN COMPOUND

2. WRITE THE IONS FOR EACH ELEMENT

3. BALANCE CHARGES USING EITHER METHOD(REDUCE IF NECESSARY)

• CHEMICAL FORMULAS FOR COMPOUNDS DO NOT HAVE CHARGES!!

• THE NUMBER OF ATOMS MUST BE SHOWN AS A SUBSCRIPT.

• REMEMBER THE SIZE AND THE SHAPE OF THE LETTERS MATTER WHEN WRITING CHEMICAL FORMULAS: COS AND COS ARE TWO DIFFERENT THINGS

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IONIC NAMES TO FORMULAS• EXAMPLES

1. STRONTIUM SULFIDE

• SR+2 S-2

• SRS

2. MAGNESIUM CYANIDE

• MG +2 CN-1

• MG(CN)2

3. POTASSIUM PHOSPHIDE

• K+1 P+3

• K3P

• Examples4. Zinc Oxide

• Zn+1 O-2• Zn2O

5. Cobalt (II) Oxide• Co+2 O-2• CoO

6. Manganese (IV) Sulfate

• Mn+4 S-2• MnS2

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FORMATION OF IONIC COMPOUNDS

• METALS LOSE THEIR ELECTRONS TO NONMETALS

• THE OPPOSITE CHARGES ATTRACT AND FORM AN IONIC BOND

NA + CL →NA + CL →NA+1 + CL-1 → NACL

NAME IS: SODIUM CHLORIDE

Mg + S →Mg + S →Mg+2 + S-2 → MgS name is: Magnesium Sulfide

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PROPERTIES OF IONIC COMPOUNDS

• IONIC COMPOUNDS FORM BY THE TRANSFER OF ELECTRONS

• MOST IONIC COMPOUNDS ARE CRYSTALLINE SOLIDS AT ROOM TEMPERATURE.

• IONS IN THE CRYSTALS ARE ARRANGED IN REPEATING THREE-DIMENSIONAL PATTERNS.

• THE LARGE ATTRACTIVE FORCES RESULT IN VERY STABLE STRUCTURES

• IONIC COMPOUNDS GENERALLY HAVE HIGH MELTING POINTS.

• IONIC COMPOUNDS CAN CONDUCT AN ELECTRIC CURRENT WHEN MELTED OR DISSOLVED IN WATER

• THE ION MOVEMENT ALLOWS ELECTRICITY TO FLOW BETWEEN ELECTRODES

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METALLIC BONDS AND METALLIC PROPERTIES

• THE VALENCE ELECTRONS OF METAL ATOMS CAN BE MODELED AS A SEA OF ELECTRONS.

• METALLIC BONDS CONSIST OF THE ATTRACTION OF THE FREE-FLOATING VALENCE ELECTRONS FOR THE POSITIVELY CHARGED METAL IONS.

• THE SEA-OF-ELECTRONS MODELS EXPLAINS MANY PHYSICAL PROPERTIES OF METALS

• METALS ARE GOOD CONDUCTORS OF ELECTRIC CURRENT BECAUSE ELECTRONS CAN FLOW FREELY IN THEM

• METALS ARE MALLEABLE (CAN BE HAMMERED OR FORCED INTO SHAPES.)

• METALS ARE DUCTILE (CAN BE DRAWN INTO WIRES)

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ALLOYS

• METAL ATOMS ARE ARRANGED IN VERY COMPACT AND ORDERLY PATTERNS

• ALLOYS ARE MIXTURES COMPOSED OF TWO OR MORE ELEMENTS, AT LEAST OF ONE WHICH IS METAL

• ALLOYS ARE IMPORTANT BECAUSE THEIR PROPERTIES ARE SUPERIOR TO THOSE OF THEIR COMPONENTS ELEMENTS.

• BRONZE ALLOY IS MADE OF COPPER AND IRON

• STEEL ALLOYS ARE MADE OF IRON AND CARBON WITH ADDITIONAL ELEMENTS.

review: what do we already know? protons determine the identinty of the element valance electrons...

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