Chapter 6:Chapter 6:

The Periodic TableThe Periodic Table

Organizing the ElementsOrganizing the Elements Demitri MendeleeveDemitri Mendeleeve (Russian – 1869) (Russian – 1869)

Published the 1Published the 1stst periodic table periodic table Based on Based on atomic massatomic mass

The Periodic LawThe Periodic Law Modern Periodic TableModern Periodic Table

Organized according to Organized according to atomic numberatomic number

Periods Periods = rows 1-7= rows 1-7 equal to the principal energy equal to the principal energy

levellevel

GroupsGroups = columns 1-18 = columns 1-18 elements have similar propertieselements have similar properties

Law:Law: Properties of elements repeat as you Properties of elements repeat as you move from move from LeftLeft → → RightRight across a period across a period

Period → Group ↓

Metallic CharacterMetallic Character Approx. 2/3 of the elements are metalsApprox. 2/3 of the elements are metals Metallic PropertiesMetallic Properties

LusterLuster ConductivityConductivity MalleabilityMalleability DuctilityDuctility Tend to lose electronsTend to lose electrons

Nonmetallic PropertiesNonmetallic Properties Dull lusterDull luster Poor conductorsPoor conductors BrittleBrittle Tend to gain electronsTend to gain electrons

Metalloids (semimetals)Metalloids (semimetals) Some properties characteristic of metals and Some properties characteristic of metals and

other properties characteristic of nonmetalsother properties characteristic of nonmetals

Metals and NonmetalsMetals and Nonmetals

Li

3

He

2

C

6

N

7

O

8

F

9

Ne

10

Na

11

B

5

Be

4

H

1

Al

13

Si

14

P

15

S

16

Cl

17

Ar

18

K

19

Ca

20

Sc

21

Ti

22

V

23

Cr

24

Mn

25

Fe

26

Co

27

Ni

28

Cu

29

Zn

30

Ga

31

Ge

32

As

33

Se

34

Br

35

Kr

36

Rb

37

Sr

38

Y

39

Zr

40

Nb

41

Mo

42

Tc

43

Ru

44

Rh

45

Pd

46

Ag

47

Cd

48

In

49

Sn

50

Sb

51

Te

52

I

53

Xe

54

Cs

55

Ba

56

He

72

Ta

73

W

74

Re

75

Os

76

Ir

77

Pt

78

Au

79

Hg

80

Tl

81

Pb

82

Bi

83

Po

84

At

85

Rn

86

Fr

87

Ra

88

Rf

104

Db

105

Sg

106

Bh

107

Hs

108

Mt

109

Mg

12

Ce

58

Pr

59

Nd

60

Pm

61

Sm

62

Eu

63

Gd

64

Tb

65

Dy

66

Ho

67

Er

68

Tm

69

Yb

70

Lu

71

Th

90

Pa

91

U

92

Np

93

Pu

94

Am

95

Cm

96

Bk

97

Cf

98

Es

99

Fm

100

Md

101

No

102

Lr

103

La

57

Ac

89

1

2

3

4

5

6

7

METALS

Nonmetals

Metalloids

Reference TableReference Table• Periodic Table Periodic Table

Trends:Trends: 1. Across a period, metallic character →1. Across a period, metallic character →

Why?Why?More electrons in outer shellsMore electrons in outer shellsLess tendency to lose electronsLess tendency to lose electrons

2. Down a group, metallic character → 2. Down a group, metallic character →

Why?Why?Less electrons in outer shellsLess electrons in outer shellsGreater tendency to lose electronsGreater tendency to lose electrons

decreases

increases

Metallic ReviewMetallic Review Identify each element as a metal, Identify each element as a metal,

nonmetal or metalloidnonmetal or metalloid

a)a) Gold -Gold -

b)b) Silicon -Silicon -

c)c) Sulfur -Sulfur -

d)d) Barium -Barium -

MetalMetalloidNonmetal

Metal

Which of these sets of elements have Which of these sets of elements have similar physical and chemical similar physical and chemical properties?properties?

a)a) oxygen, nitrogen, carbon, oxygen, nitrogen, carbon,

b)b) strontium, magnesium, calcium, strontium, magnesium, calcium, berylliumberyllium

c)c) nitrogen, neon, , fluorinenitrogen, neon, , fluorine

Name 2 elements that have properties Name 2 elements that have properties similar to those of the element similar to those of the element sodium.sodium.

Any other Group 1 element:Lithium, Potassium, Rubidium, Cesium, Francium

boronboron

nickelnickel

Identify each property below as more Identify each property below as more characteristic of a metal or a nonmetalcharacteristic of a metal or a nonmetal

a)a) Brittle -Brittle -

b)b) Malleable -Malleable -

c)c) Poor conductor of electricity -Poor conductor of electricity -

d)d) Shiny -Shiny -

e)e) Tend to gain electrons -Tend to gain electrons -

In which pair of elements are the In which pair of elements are the chemical properties of the elements most chemical properties of the elements most similar?similar?

a)a) sodium and chlorinesodium and chlorine

b)b) nitrogen and phosphorusnitrogen and phosphorus

c)c) boron and oxygenboron and oxygen

Nonmetal

MetalNonmetal

MetalNonmetal

Classifying the ElementsClassifying the Elements

Alkali MetalsAlkali Metals – – Alkaline Earth MetalsAlkaline Earth Metals – – HalogensHalogens – – Noble GasesNoble Gases – – Representative ElementsRepresentative Elements – – Transition ElementsTransition Elements – –

Group 1 (1A)Group 1 (1A)

Group 2 Group 2 (2A)(2A)Group 17 (7a)Group 17 (7a)

Group 18 (8A) Inert gasesGroup 18 (8A) Inert gases

Groups 1A – 7AGroups 1A – 7A

All Group BAll Group B

Li

3

He

2

C

6

N

7

O

8

F

9

Ne

10

Na

11

B

5

Be

4

H

1

Al

13

Si

14

P

15

S

16

Cl

17

Ar

18

K

19

Ca

20

Sc

21

Ti

22

V

23

Cr

24

Mn

25

Fe

26

Co

27

Ni

28

Cu

29

Zn

30

Ga

31

Ge

32

As

33

Se

34

Br

35

Kr

36

Rb

37

Sr

38

Y

39

Zr

40

Nb

41

Mo

42

Tc

43

Ru

44

Rh

45

Pd

46

Ag

47

Cd

48

In

49

Sn

50

Sb

51

Te

52

I

53

Xe

54

Cs

55

Ba

56

He

72

Ta

73

W

74

Re

75

Os

76

Ir

77

Pt

78

Au

79

Hg

80

Tl

81

Pb

82

Bi

83

Po

84

At

85

Rn

86

Fr

87

Ra

88

Rf

104

Db

105

Sg

106

Bh

107

Hs

108

Mt

109

Mg

12

Ce

58

Pr

59

Nd

60

Pm

61

Sm

62

Eu

63

Gd

64

Tb

65

Dy

66

Ho

67

Er

68

Tm

69

Yb

70

Lu

71

Th

90

Pa

91

U

92

Np

93

Pu

94

Am

95

Cm

96

Bk

97

Cf

98

Es

99

Fm

100

Md

101

No

102

Lr

103

La

57

Ac

89

1

2

3

4

5

6

7

Label your Reference Periodic Table…

1

2 13 14 15 16 17

18

3 4 5 6 7 8 9 10 11 12

Classifying ReviewClassifying Review Which of the following are symbols Which of the following are symbols

for representative elementsfor representative elementsNa, Mg, , Cl?Na, Mg, , Cl?

Which of these metals is Which of these metals is notnot a a transition metal?transition metal?

a)a) AluminumAluminumb)b) SilverSilverc)c) IronIrond)d) ZirconiumZirconium

Fe, NiFe, Ni

Atomic RadiusAtomic Radius Atoms are roughly sphericalAtoms are roughly spherical Sphere size can be determined using the Sphere size can be determined using the

radiusradius Problem:Problem:

Solution:Atomic Radii – half the half the distance between the distance between the nuclei of identical nuclei of identical atoms that are bonded atoms that are bonded togethertogether

Edges of orbitals are fuzzy Edges of orbitals are fuzzy and difficult to measure…and difficult to measure…

Reference Table: Reference Table: • Table STable S

Trends:Trends:1. Across a period, the atomic radius 1. Across a period, the atomic radius → →

Why?Why? Nuclei have larger positive charges Nuclei have larger positive charges Electrons are pulled in closerElectrons are pulled in closer

2. Down a group, the atomic radius 2. Down a group, the atomic radius →→

Why?Why?Greater number of energy shellsGreater number of energy shellsValence electrons are further away from the Valence electrons are further away from the nucleusnucleus

decreases

increases

Atomic Radius ReviewAtomic Radius Review Which element in each pair has a Which element in each pair has a

larger atomic radius?larger atomic radius?

a)a) & lithium& lithium

b)b) & bromine& bromine

c)c) carbon &carbon &

d)d) & neon& neon Arrange these elements in order of Arrange these elements in order of

decreasing atomic size: sulfur, decreasing atomic size: sulfur, chlorine, aluminum, and sodium.chlorine, aluminum, and sodium.

Sodium Sodium → Aluminum → Sulfur → Chlorine→ Aluminum → Sulfur → Chlorine

sodiusodiummcalciumcalcium

germaniumgermanium

fluorinefluorine

Ionization EnergyIonization Energy What is an What is an ionion??

An electrically charged atomAn electrically charged atom

Atoms may either Atoms may either gaingain or or loselose electrons electrons Loss of electrons = (+) charge Loss of electrons = (+) charge →→ Gain of electrons = (-) charge Gain of electrons = (-) charge →→

Ionization energyIonization energy ==

cationcationanionanion

the amount of energy the amount of energy requiredrequired to to remove the most loosely bound remove the most loosely bound electron electron

A + A + energyenergy A A++ + e + e--

Reference Table Reference Table • Table STable S

Trends:Trends:1. Across a period, the ionization energy 1. Across a period, the ionization energy →→

Why?Why?Electrons are held closer to the nucleus Electrons are held closer to the nucleus

Electrons are more difficult to removeElectrons are more difficult to remove

2. Down a group, the ionization energy → 2. Down a group, the ionization energy →

Why?Why?Electrons are further away from the nucleusElectrons are further away from the nucleus

Electrons are easier to removeElectrons are easier to remove

Relate Back:Relate Back:

increasincreaseses

decreasedecreasess

What type of relationship exists between What type of relationship exists between ionization energy and atomic radii?ionization energy and atomic radii?InversInvers

ee

Ionization ReviewIonization Review Which element in each pair has a Which element in each pair has a

greater ionization energy?greater ionization energy?a)a) lithium,lithium,b)b) magnesium,magnesium,c)c) cesium,cesium, Arrange the following groups in Arrange the following groups in

order of increasing ionization order of increasing ionization energy energy

a)a) Be, Mg, SrBe, Mg, Srb)b) Bi, Cs, BaBi, Cs, Bac)c) Na, Al, S Na, Al, S

boronboronstrontiumstrontium

aluminumaluminum

Be Be → Mg → Sr→ Mg → SrBi Bi → Ba → Cs→ Ba → CsNa Na → Al → S→ Al → S

Ionic SizeIonic Size CationsCations from when from when atoms atoms looseloose ee--

The cation is The cation is smallersmaller

AnionsAnions from when from when atoms atoms gain egain e--

The anion is The anion is largerlarger

Reference TableReference Table• No true tableNo true table

Trends:Trends:1. Across a period, ionic size 1. Across a period, ionic size → →

Why?Why?When eWhen e-- are lost, the attraction between the are lost, the attraction between the remaining eremaining e-- increases increasesee-- are drawn closer to the nucleus are drawn closer to the nucleus

2. Down a group, ionic size →2. Down a group, ionic size →

Why?Why?Increased atomic radiusIncreased atomic radiusee-- are further away from the nucleus are further away from the nucleus

increases

decreases

Ion Size ReviewIon Size Review Which particle has the larger radius Which particle has the larger radius

in each atom/ion pair?in each atom/ion pair?a)a) Na,Na,b)b) S,S,c)c) I,I,d)d) Al,Al, The ions NaThe ions Na++ and Mg and Mg2+2+ each have each have

10e10e--. Which ion would you expect . Which ion would you expect to have a smaller ionic radius?to have a smaller ionic radius?

MgMg2+2+ atomic radius is smaller & e atomic radius is smaller & e-- are pulled in closer are pulled in closer

NaNa++

SS2-2-

II--

AlAl3+3+

ElectronegativityElectronegativity

A measure of the ability of an atom to attract a A measure of the ability of an atom to attract a pair of electrons when bonded to another atompair of electrons when bonded to another atom

Ability to ‘pull’ electrons from another atomAbility to ‘pull’ electrons from another atom

Electrons pulled closer:

Electrons pulled away:

Reference TableReference Table• Table STable S

Trends:Trends:1. Across a period, the electronegativity 1. Across a period, the electronegativity → →

Why?Why?Atoms are very close to a stable octetAtoms are very close to a stable octet‘‘Pull’ electrons from other atomsPull’ electrons from other atoms

2. Down a group, the electronegativity →2. Down a group, the electronegativity →

Why?Why?Top atoms have few electrons, and hold them Top atoms have few electrons, and hold them tightlytightlyBottom atoms have numerous electrons and little Bottom atoms have numerous electrons and little desire to acquire moredesire to acquire more

increases

decreases

Electronegativity ReviewElectronegativity Review Which element in each pair has a Which element in each pair has a

higher electronegativity value?higher electronegativity value?a)a) Cl,Cl,b)b) C,C,c)c) Mg,Mg,d)d) As,As, Which element in each pair has a Which element in each pair has a

greater attraction for electrons? greater attraction for electrons? a)a) Ca orCa orb)b) O orO orc)c) S S

FFNN

NeNeCaCa

OOFF

or Kor K

DecreasesDecreasesIncreasesIncreasesElectronegativityElectronegativity

IncreasesIncreasesDecreasesDecreasesIon SizeIon Size

DecreasesDecreasesIncreasesIncreasesIonization Ionization EnergyEnergy

IncreasesIncreasesDecreasesDecreasesAtomic RadiusAtomic Radius

IncreasesIncreasesDecreasesDecreasesMetallic Metallic CharacterCharacter

Variation down Variation down a Groupa Group

Variation across Variation across a Perioda Period

Periodic Periodic PropertyProperty

Summary