UNIT 2: ATOMS AND ELEMENTS

Part 2 – Day 1I. Periodic Table• Trends and Comparisons• Development of the Periodic Table

Aliens ActivityNautilus shell has a repeating pattern.

Look carefully at the drawings of the ‘aliens’.

Organize all the aliens into a meaningful pattern.

Aliens Lab    Cards  

Activity: Trends in the Periodic Table Using your text, define the following

terms. Include the usual units used. Ionization energy Atomic mass Density Electronegativity Atomic radius Melting point

How to Organize…

Baseball Cards:year, team, player, card number, value ($).

Elements:when they were discovered, family, reactivity, state of matter, metal vs. non-metal, atomic mass,atomic number.

alphabetically, mass, value, density, solid or liquid or gas

Which way is CORRECT to organize the elements?Is it possible to organize the elements correctly in more than one way?

How to Organize Elements… Periodic Table Designs

Dutch Periodic Table

106

107

108

109

110

111

112

113

114

115116

117 118

Strong, Journal of Chemical Education, Sept. 1989, page 743

Dobereiner’s TriadsName

AtomicMass Name

AtomicMass Name

AtomicMass

Calcium 40Barium 137

Average 88.5

Strontium 87.6

Chlorine 35.5Iodine 127

Average 81.3

Bromine 79.9

Sulfur 32Tellurium 127.5

Average 79.8

Selenium 79.2

Johann Dobereiner ~1817

Dobereiner discovered groups of three related elements which he termed a triad.Smoot, Price, Smith, Chemistry A Modern Course 1987, page 161

Elements could be classified into groups of three, or triads.Trends in physical properties such as density, melting point, and atomic mass were observed.

Newland’s Law of Octaves

Newland’s Law of Octaves

1

LiNaK

John Newlands ~1863

Smoot, Price, Smith, Chemistry A Modern Course 1987, page 161

2

BeMg

3

BAl

4

CSi

5

NP

6

OS

7

FCl

Arranged the 62 known elements into groups of seven according to increasing atomic mass. He proposed that an eighth element would then repeat the properties of the first element in the previous group.

Periodic Table

1

2

3

4

5

6

7

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

Hf

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

1A

2A

Alkali metals

Alkali earth metals

Transition metals

Boron group

Nonmetals

Noble gases

3B 5B 6B 7B 8B 1B 2B

3A 4A 5A 6A 7A

8A

4B

Lanthanoid Series

6

7Actinoid Series

C Solid

Br Liquid

H Gas

Development of Periodic TableLaw of Triads

Law of Octaves

Elements could be classified into groups of three, or triads.Trends in physical properties such as density, melting point, and atomic mass were observed.

Arranged the 62 known elements into groups of seven according to increasing atomic mass. He proposed that an eighth element would then repeat the properties of the first element in the previous group.

J.W. Dobereiner (1829)

J.A.R. Newlands (1864)

****Lothar Meyer (1830 – 1895)

Invented periodic table independently of Mendeleev his work was not published until 1870 - one year after Mendeleev's

You looked in the mirror this morning, and this is what you saw...

Yes, it is 1870, and you are Russian Dmitri Mendeleev. For today’s activity, you will work through the same process that Menedeleev used to develop the Periodic Table.

Dmitri Mendeleev Russian Invented periodic table Organized elements by

properties Arranged elements by

atomic mass Predicted existence of

several unknown elements Element 101

Dmitri Mendeleev

Mendeleev’s Periodic Table

Period 1

Group I II III IV V VI VII VIII

H = 1

2 Li = 7 Be= 9.4 B = 11 C = 12 N = 14 O = 16 F = 19 F = 19

3 Na = 23 Mg = 24 Al = 27.3 Si = 28 P = 31 S = 32 C = 35.5

4 K = 39 Ca = 40 ? = 44 Ti = 48 V = 51 Cr = 52 Mn = 55Fe =56, Co = 59, Ni = 59

5 Cu = 63 Zn = 65 ? = 68 ? = 72 As = 75 Se = 78 Br = 80

6 Rb = 85 Sr = 87 ? Yt = 88 Zr = 90 Nb = 94 Mo = 96 ? = 100 Ru= 104, Rh = 104, Pd = 106

7 Ag = 108 Cd = 112 In = 113 Sn = 118 Sb = 122 Te = 125 J = 127

8 Cs = 133 Ba = 137 ?Di = 138 ?Ce = 140

9

10 ?Er = 178 ?La = 180 Ta = 182 W = 184Os = 195, Ir = 197,Pt = 198

11 Au = 199 Hg = 200 Tl = 204 Pb = 207 Bi = 208

12 Th = 231 U = 240

Mendeleev’s Early Periodic Table

GRUPPE I GRUPPE II GRUPPE III GRUPPE IV GRUPPE V GRUPPE VI GRUPPE VII GRUPPE VIII ___ ___ ___ ___

RH4 RH3 RH2 RH R2O RO R2O3 RO2 R2O5 RO3 R2O7 RO4 R

EIH

EN

1

2

3

4

5

6

7

8

9

10

11

12

From Annalen der Chemie und Pharmacie, VIII, Supplementary Volume for 1872, p. 151.

H = 1

Li = 7 Be = 9.4 B = 11 C = 12 N = 14 O = 16 F = 19

Na = 23 Mg = 24 Al = 27.3 Si = 28 P = 31 S = 32 Cl = 35.5

K = 39 Ca = 40 __ = 44 Ti = 48 V = 51 Cr = 52 Mn = 55 Fe = 56, Co = 59,

Ni = 59, Cu = 63(Cu = 63) Zn = 65 __ = 68 __ = 72 As = 75 Se = 78 Br = 80

Rb = 85 Sr = 87 ? Yt = 88 Zr = 90 Nb = 94 Mo = 96 __ = 100 Ru = 104, Rh = 104,

Pd = 106, Ag = 108 (Ag = 108) Cd = 112 In = 113 Sn = 118 Sb = 122 Te = 125 J = 127

Cs = 133 Ba = 137 ? Di = 138 ? Ce = 140 __ __ __ __ __ __ __

( __ ) __ __ __ __ __ __

__ __ ? Er = 178 ? La = 180 Ta = 182 W = 184 __ Os = 195, Ir = 197,

Pt = 198, Au = 199 (Au = 199) Hg = 200 Tl= 204 Pb = 207 Bi = 208 __ __

__ __ __ Th = 231 __ U = 240 __ __ __ __ __

TABELLE II

?

? ?

Elements Properties are PredictedProperty Mendeleev’s Predictions in 1871 Observed Properties

Molar Mass Oxide formula Density of oxide Solubility of oxide

Scandium (Discovered in 1877)44 gM2O3

3.5 g / mlDissolves in acids

43.7 gSc2O3

3.86 g / mlDissolves in acids

Molar mass Density of metal Melting temperature Oxide formula Solubility of oxide

Gallium (Discovered in 1875)68 g

6.0 g / mlLowM2O3

Dissolves in ammonia solution

69.4 g5.96 g / ml

30 0CGa2O3

Dissolves in ammonia

Molar mass Density of metal Color of metal Melting temperature Oxide formula Density of oxide Chloride formula Density of chloride Boiling temperature of chloride

Germanium (Discovered in 1886)72 g

5.5 g / mlDark gray

HighMO2

4.7 g / mlMCl4

1.9 g / mlBelow 100 oC

71.9 g5.47 g / ml

Grayish, white900 0CGeO2

4.70 g / mlGeCl4

1.89 g / ml86 0C

O’Connor Davis, MacNab, McClellan, CHEMISTRY Experiments and Principles 1982, page 119,

Modern Periodic Table Henry G.J. Moseley Determined the

atomic numbers of elements from their X-ray spectra (1914)

Arranged elements by increasing atomic number

Killed in WW I at age 28(Battle of Gallipoli in Turkey)

1887 - 1915

Periodic Table of the Elements

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

Hf

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

*

W

Metals and Nonmetals Metals tend to lose electrons to form positive ions. Nonmetals tend to gain electrons to form negative ions.

Alkali Metals Group 1 of the periodic table: lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr).  (Note that hydrogen, although nominally also a member of Group 1, very rarely exhibits behaviour comparable to the

alkali metals).  The alkali metals provide one of the best examples of group trends in properties in the periodic table, with well

characterized homologous behaviour down the group.

Alkali Metals The alkali metals are not at all highly reactive and are rarely found in elemental form in nature (excpet Na and K). They also tarnish easily and have low melting points and densities.  The alkali metals are silver-colored (cesium has a golden tinge), soft, low-density metals, which react readily with halogens to form ionic salts, and with water to form strongly alkaline (basic)

hydroxides.   These elements all have one electron in their outermost shell, so the energetically preferred state of achieving a filled electron shell is to lose one electron to form a singly charged positive ion.

 

Alkaline Earth Metals Group 2 of the periodic table: beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba) and radium

(Ra). The alkaline earth metals provide a good example of group trends in properties in the periodic table, with well-

characterized homologous behaviour down the group.  

Alkaline Earth Metals The alkaline earth metals are silvery colored, soft, low-density metals, which react readily with halogens to form

ionic salts, and with water, though not as rapidly as the alkali metals, to form strongly alkaline (basic) hydroxides. For example, where sodium and potassium react with water at room temperature, magnesium reacts only with steam and calcium with hot water.

 Beryllium is an exception: It does not react with water or steam, and its halides are covalent.

Alkaline Earth Metals All the alkaline earth metals have two electrons in their outermost shell, so the energetically preferred state of

achieving a filled electron shell is to lose two electrons to form doubly charged positive ions.  The alkaline earth metals are named after their oxides, the alkaline earths. These oxides are basic (alkaline) when

combined with water. "Earth" is an old term applied by early chemists to nonmetallic substances that are insoluble in water and resistant to heating--properties shared by these oxides.

Lanthanides The lanthanide series comprises the 15 elements with atomic numbers 57 through 71 The name "rare earths" is sometimes used to describe all the lanthanides These elements are in fact fairly abundant in nature. Most lanthanides are widely used in lasers. These elements deflect UV and Infrared electromagnetic radiation and are commonly used in the production of sunglass lenses. Lanthanides are shiny and silvery-white. They are relatively soft. Many are used to make steel. They react violently with most nonmetals.

Actinides The actinides encompasses the 15 chemical elements that lie between actinium and lawrencium  All actinides are radioactive.  Only thorium and uranium occur naturally in the earth's crust  The remaining actinides were discovered in nuclear fallout, or were synthesized in particle colliders

Non Metals The nonmetals are generally to:  Hydrogen (H) Carbon (C) Nitrogen (N), Phosphorus (P) Oxygen (O), Sulfur (S), Selenium (Se) the halogens the noble gases

Non Metals Common properties considered characteristic of a nonmetal include: poor conductors of heat and electricity when compared to metals they form acidic oxides (whereas metals generally form basic oxides) in solid form, they are dull and brittle, rather than metals which are lustrous, or malleable usually have lower densities than metals they have significantly lower melting points and boiling points than metals  

Non Metals Nonmetals make up most of the crust, atmosphere and oceans of the earth. Bulk tissues of living organisms are

composed almost entirely of nonmetals.

Many nonmetals (hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine, and iodine) are diatomic (two atoms in one molecule- O2)

Nobel Gases The noble gases are the elements in group 18 of the periodic table. They are the most stable due to having the maximum

number of valence electrons their outer shell can hold. Therefore, they rarely react with other elements since they are already stable. Other characteristics of the noble gases are that they all conduct electricity, fluoresce, are odorless and colorless, and are used in many conditions when a stable element is needed to maintain a safe and constant environment.

 

Nobel Gases All of them exhibit an extremely low chemical reactivity; in fact no conventional compounds of helium or neon have yet been prepared. Xenon and

krypton are known to show some reactivity in the laboratory. Recently argon compounds have also been successfully characterised.  The noble gases have high ionization energies and small electronegativities.  The noble gases have very weak inter-atomic forces of attraction, and consequently very low melting points and boiling points. This is why they

are all monoatomic gases under normal conditions, even those with larger atomic masses than many normally solid elements.  

Nobel Gases One of the most commonly encountered uses of the noble gases in everyday life is in lighting. Argon is often

used as a suitable safe and inert atmosphere for the inside of filament light bulbs. Some of the noble gases glow distinctive colors when used inside lighting tubes (neon lights). Helium, due to its non-reactivity (compared to flammable hydrogen) and lightness, is often used in blimps and balloons. Krypton is also used in lasers, and is used by doctors for eye surgery.

Periodic Table Assignment From the handout, do the following questions:

#11 – 14, 8, 9, 17