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The Periodic Table

Development of the Modern Periodic TableAntione Laviosier- 1st list of elementsJohn Newlands:arranged by increasing atomic mass,

the properties repeat every 8 elements (law of octaves) Mendeleev :Mendeleev : based on the similarity of properties and based on the similarity of properties and

reactivities exhibited by certain elements using atomic reactivities exhibited by certain elements using atomic mass; able to predict properties of unknown elementsmass; able to predict properties of unknown elements

Henri Moseley:Henri Moseley: each elements has a unique atomic each elements has a unique atomic number, which is how the current periodic table is number, which is how the current periodic table is organized.organized.

http://www.chem.msu.su/eng/misc/mendeleev/welcome.html

Development of the Modern Periodic Table

The columns: groups/families The rows: periods Group A elements:representative/main group

elements Groups 1,2, 13-18 Blocks s & p

Group B elements:transition & inner transition Groups 3-12 Blocks d & f

3 Main Classifications of Elements:

1. Metals – shiny, smooth, solid at room temperature, good conductors of heat and electricity, ductile, malleable mostly group 1 and 2 and B (left of periodic table)Group 1 – alkali metalsGroup 2 – alkaline earth metalsGroup B are transition and inner transition

(lanthanide and actinide series)

Development of the Modern Periodic Table

2. Nonmetals: upper right side of the periodic tableUsually gases or brittle dull solids, poor

conductors of heat and electricityOnly bromine is liquid at room

temperatureHalogens: Group 17 & highly reactiveNoble gases: Group 18 & non-reactive

3. Metalloids: border stair step – have properties of both metals and nonmetalsUsed in computer chips and solar cells

Development of the Modern Periodic Table

1IA

18VIIIA

12

IIA13

IIIA14

IVA15VA

16VIA

17VIIA

2

33

IIIB4

IVB5

VB6

VIB7

VIIB8 9

VIIIB10 11

IB12IIB

4

5

6

7

MetalsMetalsNonmetalsNonmetals

Classification of the elements Valence electrons Atoms in groups have similar chemical properties

because they have the same # of valence electrons Remember s,p,d &f blocks of the periodic table

B2p1

I1A

18VIIIA

1 14IVA

15VA

16VIA

17VIIA

2

3 3IIIB

4IVB

5VB

6VIB

7VIIB

8 9VIIIB

10 11IB

12IIB

4

5

6

7

H1s1

Li2s1

Na3s1

K4s1

Rb5s1

Cs6s1

Fr7s1

Be2s2

Mg3s2

Ca4s2

Sr5s2

Ba6s2

Ra7s2

Sc3d1

Ti3d2

V3d3

Cr4s13d5

Mn3d5

Fe3d6

Co3d7

Ni3d8

Zn3d10

Cu4s13d10

B2p1

C2p2

N2p3

O2p4

F2p5

Ne2p6

He1s2

Al3p1

Ga4p1

In5p1

Tl6p1

Si3p2

Ge4p2

Sn5p2

Pb6p2

P3p3

As4p3

Sb5p3

Bi6p3

S3p4

Se4p4

Te5p4

Po6p4

Cl3p5

Be4p5

I5p5

At6p5

Ar3p6

Kr4p6

Xe5p6

Rn6p6

Y4d1

La5d1

Ac6d1

Cd4d10

Hg5d10

Ag5s14d10

Au6s15d10

Zr4d2

Hf5d2

Rf6d2

Nb4d3

Ta5d3

Db6d3

Mo5s14d5

W6s15d5

Sg7s16d5

Tc4d5

Re5d5

Bh6d5

Ru4d6

Os5d6

Hs6d6

Rh4d7

Ir5d7

Mt6d7

Ni4d8

Ni5d8

2IIA

Periodic Trends

Atomic Radius: (atoms without charge) ½ the distance across atom Decreases left to right because of the pull from the nucleus

as the outer energy level fills Increase top to bottom because of the additional energy level

Periodic Trends

Shielding- when levels of electrons “block” the pull of the nucleus from the outer electrons

As you go across the periodic table, shielding does not change

As you go down a period, shielding increases b/c you have added a level

Periodic Trends

Atomic Radius Questions: Which has a large atomic radius: Li or Ne? Why? Which has a smaller atomic radius: Na or Cs? Why?

Periodic Trends

Ionic Radius Ions are atoms with a charge - #p+ do not equal #e-

Remember that “stable” atoms/ions have 8 e- (octet rule) Atoms will gain, lose, or share e- to get 8

Groups 1 – 14 lose an e- becoming positively charged and they get smaller (metals)

Groups 15-17 gain e- becoming negatively charged and they get bigger (nonmetals)

Which is larger Na or Na+? Why? Which is smaller Br or Br-? Why?

Periodic Trends

Ionization energy: The energy required to remove the valence electron from an atom in the gaseous state Increases left to right because the electron is closer to the

nucleus Decrease going down because the electron is further from

the nucleus

Periodic Trends

Electronegativity :The ability of an atom to attract e- when bonded in units of Paulings F is most electronegative because F is smallest with

the most pull from the nucleus Fr is least electronegative because Fr is largest with

least pull from the nucleus

Periodic Trends

1H

3Li

11Na

19K

37Rb

55Cs

87Fr

4Be

12Mg

20Ca

38Sr

56Ba

88Ra

21Sc

39Y

57La

89Ac

22Ti

40Zr

72Hf

104Rf

23V

41Nb

73Ta

105Db

42Mo

74W

106Sg

25Mn

43Tc

75Re

107Bh

26Fe

44Ru

76Os

108Hs

27Co

45Rh

77Ir

109Mt

28Ni

46Pd

78Pt

110Uun

111Uuu

30Zn

48Cd

80Hg

8O

16S

34Se

52Te

84Po

7N

15P

33As

51Sb

83Bi

6C

14Si

32Ge

50Sn

82Pb

5B

13Al

31Ga

49In

81Tl

9F

17Cl

35Br

53I

85At

2He

10Ne

18Ar

36Kr

54Xe

86Rn

24Cr

29Cu

47Ag

79Au

112Uub

114Uuq

116Uuh

118Uuo

Ele

ctro

nega

tivity

dec

reas

esIo

niza

tion

ener

gy d

ecre

ases

Ato

mic

rad

ius

incr

ease

s

Electronegativity increasesIonization energy increasesAtomic radius decreases

Properties of the s-Block Elements

Diagonal Relationships – some period 2 elements behave more like the period 3 elements in the next group than what is expected based on their position. Li behaves like Mg B behaves like Si Be behaves like Al

Properties of s-Block Elements

H is in group 1 because it has 1 valence electron It has metallic and non metallic properties

Metal: loses an e-

Non-metal: gas, increase reactivity (like halogens) gains an e-

Properties of s-Block Elements

Alkali Metals: Group 1React with water to form alkaline solutions,

lose 1 valence e- becoming a 1+ ion, soft metal, highly reactive, the best conductors of heat and electricity

So reactive that they must be stored under oil

Properties of s-Block Elements

Alkaline Earth Metals: Group 2 Shiny solids, harder than alkali metals, less

reactive then alkali metals, lose 2 valence e- becoming a 2+ ion, good conductors of heat and electricity, react with water

Properties of p-Block Elements

Group 13: The “Boron” Group Boron is a metalloid, the rest are metals

B, Al, Ga, In lose 3 valence e-

Tl loses 1p valence e- (Ga and In can too) Group 14: The “Carbon” Group

C is a nonmetal, Si and Ge are metalloids, Sn and Pb are metals

Properties of p-Block Elements

Mineral: found in nature as solid crystals Ore:material that can be removed at a reasonable

cost Allotrope: forms of an element in the same

physical state – solid, liquid, or gas – that have different structures and properties Diamond, graphite, and coal

Properties of p-Block Elements

Group 15: The “Nitrogen” Group N and P are nonmetals and gain 3 e- to become a 3-

charged ion As and Sb are metalloids Bi is a metal and loses 3 e- to become a 3+ charged

ion Group 16: The “Oxygen” Group

6 valence e-, gain 2 e- to become ions with a 2-charge O, S, and Se are nonmetals Te and Po are metalloids

Properties of p-Block Elements

Group 17: Halogens – “salt formers” Combine with metals to form salts Form ions with a 1-charge by gaining 1 e-

Group 18: Noble gases Colorless, un-reactive, full valence e-

Homework: page 206 #39, 41, 45, 49

Properties of the d and f-Block Elements

Transition metals Electric conductors, have luster and malleability Little variation in atomic size, electronegativity, and

ionization energy across a period More unpaired e- in d orbital, the increase in hardness

and melting points Varied ions due to access of d orbital – all lose e-

Inner Transition Lanthanide – silvery metals with increased melting

point Homework: page 206 # 57, 59-61, 69

Properties of the d and f-Block Elements

Magnetism – ability to be affected by magnet Diamagnetism – all e- are paired, substance is

unaffected or slightly repelled by magnetic field Paramagnetic – unpaired electron in the valence orbital

is attracted to magnetic field Ferromagnetism – strong attraction of substance, ions

can align in direction of field and form permanent magnet