Transcript Ionic Bonding and Naming

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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BONDING
CHEMISTRY 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
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B. TYPES OF BONDS
IONIC
COVALENT
Bond
Formation
e- are transferred from
metal to nonmetal
e- are shared between
two nonmetals
Type of
Structure
crystal lattice
true molecules
Physical
State
solid
liquid or gas
Melting
Point
high
low
Solubility in
Water
yes
usually not
Electrical
Conductivity
yes
(solution or liquid)
no
Other
Properties
odorous
B. TYPES OF BONDS
METALLIC
Bond
Formation
e- are delocalized
among metal atoms
Type of
Structure
“electron sea”
Physical
State
solid
Melting
Point
very high
Solubility in
Water
no
Electrical
Conductivity
yes
(any form)
Other
Properties
malleable, ductile,
lustrous
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.
C. BOND POLARITY
• NONPOLAR COVALENT BOND
• E- ARE SHARED EQUALLY
• SYMMETRICAL E- DENSITY
• USUALLY IDENTICAL ATOMS
C. BOND POLARITY
• POLAR COVALENT BOND
• E- ARE SHARED UNEQUALLY
• ASYMMETRICAL E- DENSITY
• RESULTS IN PARTIAL CHARGES (DIPOLE)
+


C. BOND POLARITY
Nonpolar
Polar
Ionic
View Bonding Animations.
C. BOND POLARITY
EXAMPLES:
• CL2
• HCL
• NACL
3.0-3.0=0.0
Nonpolar
3.0-2.1=0.9
Polar
3.0-0.9=2.1
Ionic
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
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ITS EFFECT ON THE ATOM’S CHEMICAL PROPERTIES.
IONIC BONDING AND NAMING
A. IONIC NOMENCLATURE
COMMON ION CHARGES
1+
0
2+
3+ NA 3- 2- 1-
IONIC BONDING AND NAMING
A. VOCABULARY
ION
1 atom
2 or more atoms
Monatomic
Ion
Polyatomic
Ion
+
Na
NO3
-
IONIC BONDING AND NAMING
A. VOCABULARY
COMPOUND
2 elements
Binary
Compound
NaCl
more than 2
elements
Ternary
Compound
NaNO3
IONIC BONDING AND NAMING
FORMATION 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 NAMING
B. 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.Carbon
2.Calcium
3.Chlorine
4.Argon
4 valance e2 valance e7 valance e8 valance e-
C
Ca
Cl
Ar
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IONIC BONDING AND NAMING
B. LEWIS STRUCTURES
• IONIC – SHOW TRANSFER OF E-
IONIC BONDING AND NAMING
D. 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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IONIC BONDING AND NAMING
D. FORMULA WRITING
• 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)
(# METAL) +3 +(#NONMETAL) -3 = 0 SOLVE
(1) +3 +(1) -3 = 0
GIVES ALN
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IONIC BONDING AND NAMING
D. FORMULA WRITING
• 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
(# METAL) +2 +(#NONMETAL) -4 = 0 SOLVE
(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
(# METAL) +2 +(#NONMETAL) -3 = 0 SOLVE
(3) +2 +(2) -3 = 0
GIVES AL3(PO4)2
MUST USE PARENTHESIS TO SHOW HAVING 2 PHOSPHATE MOLECULES.
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IONIC BONDING AND NAMING
E. 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.
IONIC BONDING AND NAMING
E. IONIC NOMENCLATURE
• 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!
IONIC BONDING AND NAMING
E. IONIC NOMENCLATURE
COMMON ION CHARGES
1+
0
2+
3+ NA 3- 2- 1-
IONIC BONDING AND NAMING
E. IONIC NOMENCLATURE
potassium chloride

K+ Clmagnesium nitrate
KCl
Mg2+ NO3
copper(II) chloride
Mg(NO3)2
Cu2+ Cl-

CuCl2
IONIC BONDING AND NAMING
E. IONIC NOMENCLATURE
NaBr
sodium bromide
Na2CO3
sodium carbonate
FeCl3
iron(III) chloride
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:
4.
a.
POLYATOMIC ION WRITE IT’S SPECIAL NAME
b.
SINGLE NONMETAL ELEMENT WRITE ITS ROOT NAME FOLLOWED BY “IDE”
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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IONIC NAMING – TYPE 1
1.
KCL
2.
ALCL3
3.
CA2C
4.
INN
5.
RB3PO3
6.
AL(OH)3
7.
IN2(SO3)3
8.
(NH4)3BR
1.
2.
3.
4.
5.
6.
7.
8.
Potassium chloride
Aluminum chloride
Calcium carbide
Indium nitride
Rubidium phosphite
Aluminum hydroxide
Indium sulfite
** Ammonium bromide
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IONIC NAMING – TYPE 2 METALS
• 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,
FROM A +2 OR +1 ION
COPPER CAN
• 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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IONIC NAMING – TYPE 2 METALS
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:
4.
a.
POLYATOMIC ION WRITE IT’S SPECIAL NAME
b.
SINGLE NONMETAL ELEMENT WRITE ITS ROOT NAME FOLLOWED BY “IDE”
WRITE BOTH PARTS OF NAME SIDE BY SIDE
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IONIC NAMING – TYPE 2
• 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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IONIC NAMING – TYPE 2
• 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)
3.
O IS NOT A POLYATOMIC SO IT BECOMES OXIDE
4.
FEO IS IRON (III) OXIDE
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IONIC NAMING – TYPE 2
• 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
3.
O IS NOT A POLYATOMIC SO IT BECOMES OXIDE
4.
AG2O IS SLIVER OXIDE
REMEMBER ZN+2, CD+2, AG+1 DO NOT NEED ROMAN NUMERALS
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C. IONIC NOMENCLATURE
IONIC 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.
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
• Examples
1. STRONTIUM SULFIDE
4. Zinc Oxide
•
SR+2 S-2
•
SRS
2. MAGNESIUM CYANIDE
•
MG
•
MG(CN)2
+2
CN-1
3. POTASSIUM
PHOSPHIDE
•
K+1
•
•
Zn+1 O-2
Zn2O
5. Cobalt (II) Oxide
•
•
Co+2
CoO
O-2
6. Manganese (IV) Sulfate
•
•
Mn+4 S-2
MnS2
P+3
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•
K3P
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 → Mg
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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43
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.
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