78
History of the Atom Scientists and Their Discoveries

History of the Atom Scientists and Their Discoveries

Embed Size (px)

Citation preview

Page 1: History of the Atom Scientists and Their Discoveries

History of the Atom

Scientists and Their Discoveries

Page 2: History of the Atom Scientists and Their Discoveries

Democritus(460 BC – 370 BC)

• Proposed an Atomic Theory which states that all atoms are small, hard, indivisible and indestructible particles made of a single material formed into different shapes and sizes.

• Aristotle did not support his atomic theory

Image taken from: https://reich-chemistry.wikispaces.com/T.+Glenn+Time+Line+Project

Page 3: History of the Atom Scientists and Their Discoveries

Antoine Lavoisier (1743 – 1794)

Known as the “Father of Modern Chemistry”

Was the first person to generate a list of thirty-three elements in his textbook

Devised the metric system Married to a 13-year old

Marie-Anne Pierette Paulze; she assisted him with much of his work

Was guillotined during the French Revolution

Discovered/proposed the Law of Conservation of Mass

Image taken from: www.ldeo.columbia.edu/.../v1001/geotime2.html

Page 4: History of the Atom Scientists and Their Discoveries

John Dalton (1766 – 1844)

In 1803, proposed an Atomic Theory which states:o All substances are made of

atoms; atoms are small particles that cannot be created, divided, or destroyed.

o Atoms of the same element are exactly alike, and atoms of different elements are different

o Atoms join with other atoms to make new substances

Calculated the atomic weights of many various elements

Image taken from: chemistry.about.com/.../John-Dalton.htm

Page 5: History of the Atom Scientists and Their Discoveries

J.J. Thomson (1856 – 1940)

Proved that an atom can be divided into smaller parts

Discovered electrons Stated that the atom is neutral In 1897, proposed the Plum

Pudding Model which states that atoms mostly consist of positively charged material with negatively charged particles (electrons) located throughout the positive material

Won a Nobel Prize

Image taken from: www.wired.com/.../news/2008/04/dayintech_0430

Page 6: History of the Atom Scientists and Their Discoveries

Ernest Rutherford (1871 – 1937)

In 1909, suggested the following characteristics of the atom:o Has a nucleus that contains

most of the mass of the atom and is made up of particles called protons, which have a positive charge

o The protons are surrounded by negatively charged electrons, but most of the atom is actually empty space

Did extensive work on radioactivity and was referred to as the “Father of Nuclear Physics”

Won a Nobel Prize Was a student of J.J. Thomson

Image taken from: http://www.scientific-web.com/en/Physics/Biographies/ErnestRutherford.html

Page 7: History of the Atom Scientists and Their Discoveries

Niels Bohr (1885 – 1962)

In 1913, proposed the Bohr Model, which suggests that electrons travel around the nucleus of an atom in orbits or definite paths. Additionally, the electrons can jump from a path in one level to a path in another level (depending on their energy)

Won a Nobel Prize Worked with Ernest Rutherford

Image taken from: commons.wikimedia.org/wiki/File:Niels_Bohr.jpg

Page 8: History of the Atom Scientists and Their Discoveries

Erwin Schrodinger (1887-1961)

• In 1926, he further explained the nature of electrons in an atom:– The exact location of an

electron cannot be stated– It is more accurate to view

the electrons in regions called electron clouds; electron clouds are places where the electrons are likely to be found

• Won a Nobel Prize Image taken from:

nobelprize.org/.../1933/schrodinger-bio.html

Page 9: History of the Atom Scientists and Their Discoveries

James Chadwick (1891 – 1974)

Realized that the atomic mass of most elements was double the number of protons discovery of the neutron in 1932

Worked on the Manhattan Project

Worked with Ernest Rutherford Won a Nobel Prize

Image taken from: www.wired.com/.../news/2009/02/dayintech_0227

Page 10: History of the Atom Scientists and Their Discoveries

The Building Blocks of Matter: AtomsAtoms

+

++

+

+++

-

-

-

-

--

-

-+

Page 11: History of the Atom Scientists and Their Discoveries

Matter

• Anything that has mass and takes up space (volume)– Examples:

• A brick has mass and takes up space • A desk has mass and takes up space• A pencil has mass and takes up space• Air has mass and takes up space

All of the above examples are considered matter because they have mass and take up space. Can you think of anything that would not be considered matter?

Page 12: History of the Atom Scientists and Their Discoveries

Atoms

• Atoms- smallest possible unit into which matter can be divided, while still maintaining its properties.

• Made up of:– protons– neutrons– electrons

• The solar system is commonly used as an analogy to describe the structure of an atom

For example, what is the smallest possible unit

into which a long essay can be divided and still have some meaning?

+

-++

+

-

-

- -+

Page 13: History of the Atom Scientists and Their Discoveries

Atoms are so small that…• A stack of 50,000 aluminum

atoms = the thickness of a sheet of aluminum foil from your kitchen.

• If you could enlarge a penny until it was as wide as the US, each of its atoms would be only about 3 cm in diameter – about the size of a ping-pong ball

• Human hair is about 1 million carbon atoms wide.

• Typical human cell contains roughly 1 trillion atoms.

• A speck of dust might contain 3x1012 (3 trillion) atoms.

• It would take you around 500 years to count the number of atoms in a grain of salt.

www.deckersfoods.com

C-C-C-C-C-… + 999,995 more

1 trillion atoms

. Is made of approximately 3 trillion atoms

Just one of these grains

Page 14: History of the Atom Scientists and Their Discoveries

Let’s Experiment

In order to try to gain an idea of how small an atom really is, you will complete the following activity.

1. Cut a strip of 11 in. paper in half.2. Discard one half.3. Cut the remaining piece in half.4. Continue cutting the pieces in half and

discarding the strips as many times as you can, counting the number of cuts you make

Page 15: History of the Atom Scientists and Their Discoveries

Results

• How many cuts were you able to make?

• Do you think you could keep cutting the paper forever? Why or why not?

You would have to cut the paper in half around 31 times to get to the

size of any atom.

http://www.miamisci.org/af/sln/phantom/papercutting.html

Page 16: History of the Atom Scientists and Their Discoveries

Protons (+)

• Protons- positively charged particles

• Make up part of the nucleus of the atom

• Identify the atom • Equal to the atomic

number of the atom• Contribute to the

atomic mass• Equal to the number

of electrons+

+

+++

+++

-

-

-

-

--

-

-+

Page 17: History of the Atom Scientists and Their Discoveries

Neutrons

• Neutrons- neutral particles; have no electric charge

• Help make up the nucleus of the atom

• Contribute to the atomic mass

+

+++

+++

-

-

-

-

--

-

-+

Page 18: History of the Atom Scientists and Their Discoveries

Electrons (-)• Electrons- negatively charged

particles• Found outside the nucleus of

the atom in electron orbits/levels

• Each orbit/level can hold a maximum number of electrons

1st = 2, 2nd = 8, 3rd = 8 • When the orbitals are full,

the atoms are stable! • This Octet Rule for atoms

with < 20 electrons is 2, 8, 8, 8

• > 20 disregard

-

+

+++

+++

-

-

-

-

--

-

-+

Page 19: History of the Atom Scientists and Their Discoveries

Electrons (-)

•Move so rapidly they create an electron cloud•Mass is insignificant•Equal to the number of protons•Valence electrons- the outermost electrons involved in the formation of chemical bonds

Page 20: History of the Atom Scientists and Their Discoveries

The Atom’s “Center”

• Protons and neutrons are grouped together to form the “center” or nucleus of an atom.

-

+++

Notice that the electrons are not apart of the nucleus

--

Page 21: History of the Atom Scientists and Their Discoveries

QUARKS

• Particles that make up protons and neutrons

Notice the smaller

particles that make up this neutron after

you take a closer look.

+Notice the

smaller particles that make up this proton after you take a closer look.

What do you notice about the numberof quarks in the neutron and proton?

Page 22: History of the Atom Scientists and Their Discoveries

Sub-Atomic Particles Weight Comparison

(protons, neutrons, electrons)Neutron = 1.6749286 x10-27 kgProton = 1.6726231 x10-27 kgElectron = 9.1093897 x10-31 kg

+

-+

----- - -

--

---

--

--

-

- ----- - -

--

---

--

--

-

1836 electrons = 1 proton1839 electrons = 1 neutron

How do you think the mass of a neutron compares to that of a proton?

1 neutron ≈ 1 proton

Page 23: History of the Atom Scientists and Their Discoveries

Sub-atomic ParticlesSize Comparison

(protons, neutrons, electrons, & quarks)

Size in atoms

Size in meters

(m)

Atom 1 10-10

Nucleus __1__10,000

10-14

Proton or

Neutron

___1___100,000

10-15

Electron or

Quark

_____1____100,000,000

10-18

(at largest)

+

++

+

+++

-

-

-

-

--

-

-+

Page 24: History of the Atom Scientists and Their Discoveries

Something to Think About

• You’ll never see life the same way again

Page 25: History of the Atom Scientists and Their Discoveries

Elements

• Element- made up of one kind of atom that can’t be broken down into simpler substances by physical or chemical means

• 90 occur naturally on Earth

• 25 were synthesized (made) by scientists

118

Uuo117

Uus116Uuh(292)

115

Uup(288)

114

Uuq(289)

113

Uut(284)

112Uub(285)

111

Rg(272)

110

Ds(269)

109

Mt(268)

108

Hs(269)

107

Bh(264)

106

Sg(266)

105

Db(262)

104

Rf(261)

103

Lr(262)

88

Ra(226)

87

Fr(223)

86

Rn(222)

85

At(210)

84

Po(209)

83

Bi208.980

82

Pb207.2

81

Tl204.383

80

Hg200.59

79

Au196.967

78

Pt195.078

77

I r192.217

76

Os190.23

75

Re186.207

74

W183.84

73

Ta180.95

72

Hf178.49

71

Lu174.967

56

Ba137.327

55

Cs132.905

54

Xe131.29

53

I126.904

52

Te127.60

51

Sb121.760

50

Sn118.710

49

I n114.818

48

Cd112.4

47

Ag107.868

46

Pd106.42

45

Rh102.906

44

Ru101.07

43

Tc(98)

42

Mo95.94

41

Nb92.906

40

Zr91.224

39

Y88.906

38

Sr87.62

37

Rb85.468

36

Kr83.80

35

Br79.904

34

Se78.96

33

As74.922

32

Ge72.61

31

Ga69.723

30

Zn65.39

29

Cu63.546

28

Ni58.69

27

Co58.933

26

Fe55.845

25

Mn54.938

24

Cr51.996

23

V50.942

22

Ti47.87

21

Sc44.956

20

Ca40.078

19

K39.098

118

Uuo117

Uus116Uuh(292)

115

Uup(288)

114

Uuq(289)

113

Uut(284)

112Uub(285)

111

Rg(272)

110

Ds(269)

109

Mt(268)

108

Hs(269)

107

Bh(264)

106

Sg(266)

105

Db(262)

104

Rf(261)

103

Lr(262)

88

Ra(226)

87

Fr(223)

86

Rn(222)

85

At(210)

84

Po(209)

83

Bi208.980

82

Pb207.2

81

Tl204.383

80

Hg200.59

79

Au196.967

78

Pt195.078

77

I r192.217

76

Os190.23

75

Re186.207

74

W183.84

73

Ta180.95

72

Hf178.49

71

Lu174.967

56

Ba137.327

55

Cs132.905

54

Xe131.29

53

I126.904

52

Te127.60

51

Sb121.760

50

Sn118.710

49

I n114.818

48

Cd112.4

47

Ag107.868

46

Pd106.42

45

Rh102.906

44

Ru101.07

43

Tc(98)

42

Mo95.94

41

Nb92.906

40

Zr91.224

39

Y88.906

38

Sr87.62

37

Rb85.468

36

Kr83.80

35

Br79.904

34

Se78.96

33

As74.922

32

Ge72.61

31

Ga69.723

30

Zn65.39

29

Cu63.546

28

Ni58.69

27

Co58.933

26

Fe55.845

25

Mn54.938

24

Cr51.996

23

V50.942

22

Ti47.87

21

Sc44.956

20

Ca40.078

19

K39.098

102

No(259)

101

Md(258)

100

Fm(257)

99

Es(252)

98

Cf(251)

97

Bk(247)

96

Cm(247)

95

Am(243)

94

Pu(244)

93

Np(237)

92

U238.029

91

Pa231.036

90

Th232.038

89

Ac(227)

70

Yb173.04

69

Tm168.934

68

Er167.26

67

Ho164.930

66

Dy162.50

65

Tb158.925

64

Gd157.25

63

Eu151.964

62

Sm150.36

61

Pm(145)

60

Nd144.24

59

Pr140.908

58

Ce140.116

57

La138.906

102

No(259)

101

Md(258)

100

Fm(257)

99

Es(252)

98

Cf(251)

97

Bk(247)

96

Cm(247)

95

Am(243)

94

Pu(244)

93

Np(237)

92

U238.029

91

Pa231.036

90

Th232.038

89

Ac(227)

70

Yb173.04

69

Tm168.934

68

Er167.26

67

Ho164.930

66

Dy162.50

65

Tb158.925

64

Gd157.25

63

Eu151.964

62

Sm150.36

61

Pm(145)

60

Nd144.24

59

Pr140.908

58

Ce140.116

57

La138.906

12

Mg24.305

11

Na22.990

4

Be9.012

3

Li6.941

12

Mg24.305

11

Na22.990

4

Be9.012

3

Li6.941

1

H1.008

1

H1.008

2

He4.003

2

He4.003

18

Ar39.948

17

Cl35.453

16

S32.066

15

P30.974

14

Si28.086

13

Al26.982

18

Ar39.948

17

Cl35.453

16

S32.066

15

P30.974

14

Si28.086

13

Al26.982

10

Ne20.180

9

F18.998

8

O15.999

7

N14.007

6

C12.001

5

B10.811

10

Ne20.180

9

F18.998

8

O15.999

7

N14.007

6

C12.001

5

B10.811

1

2

3

4

5

6

7

1

2

3 4 5 6 7 8 9 10 11 12

13 14 15 16 17

18

Lanthanides

Actinides

Page 26: History of the Atom Scientists and Their Discoveries

The Periodic Table Elements

• Boxes in the periodic table contain a lot of information. To understand this information, it is necessary to refer to the periodic table’s key

Atomic Number

Element Symbol (a capital letter or a capital followed by a lower case letter)

Atomic Mass

8

O

Oxygen

15.999

Element Name

Page 27: History of the Atom Scientists and Their Discoveries

Atomic Number• Atomic number- the number of protons in the nucleus of

an atom• Equal to the number of electrons to make an atom neutral

+++

--

-

What would be the atomic

number of this atom?

Page 28: History of the Atom Scientists and Their Discoveries

Atomic Mass• Atomic mass- the total number of protons and

neutrons in an atom’s nucleus• Expressed in Atomic Mass Units (amu)• Each proton or neutron has a mass of 1 amu

+++

-

-

-What would be the atomic mass of this

atom?+ 3

4

3 protons + 4 neutrons = an atomic mass of 7

amu

Why did we not account for the electrons when calculating

the atomic mass?

Page 29: History of the Atom Scientists and Their Discoveries

How to Obtain the Number of Sub-Atomic Particles in an atom using a Periodic Table

Protons Neutrons Electrons

Equal to the atomic # on the Periodic Table

Equal to the atomic mass (rounded to a whole #)

minus the # of protons

Equal to the # of protons

Example: Determine the # of protons, neutrons, and electrons in an atom of oxygen.

Protons = 8 (Atomic #) Neutrons = 8 (Rounded atomic mass minus atomic #) Electrons = 8 (# of P)

Neutron Calculations = 16 (P + N) – 8 (P) = 8 N

+

++

+

+++++

-

= 8

= 8

= 8

-

-

-

-

--

-

-

+ -

Page 30: History of the Atom Scientists and Their Discoveries

Building Atoms

Atoms Protons Neutrons Electrons

Carbon 6 6 6

Beryllium

4 5 4

Oxygen 8 8 8

Lithium 3 4 3

Sodium 11 12 11

Page 31: History of the Atom Scientists and Their Discoveries

Hydrogen (H) Atom• Bohr electron diagrams- show ALL the electrons in

an atom. Notice the 1 electron in the 1st orbital• The rule is 2 in the first orbital, then 8, 8 = full and

stable (unreactive)

+

-

Even though there are no neutrons present, Hydrogen is still considered an atom

+

-

= 1

= 0

= 1

How manymore

electronscan fit in the 1st orbital/ level?

Page 32: History of the Atom Scientists and Their Discoveries

Oxygen (O) Atom• Notice the two electrons in the first

orbital/level and the six in the second

+

++

+

+++

-

-

-

-

--

-

-+

+

-

= 8

= 8

= 8

How manymore

electronscan fit in the 2nd orbital/ level?

Page 33: History of the Atom Scientists and Their Discoveries

Sodium (Na) Atom• Notice the two electrons in the first orbital/level,

eight in the second, and one in the third

+

++

+

+++

-

-

-

-

--

-

-+

-

-

-

+

-

= 11

= 12

= 11

How manymore

electronscan fit in the 3rd orbital/ level?

Page 34: History of the Atom Scientists and Their Discoveries

Lewis Structure(Electron Dot Diagram)

• Valence electrons- the electrons in the outermost shell that are responsible for how an atom will behave chemically

• Lewis Dot Structure- way of drawing ONLY the valence electrons of an atom

• Element symbol surrounded by as many dots as there are valence electrons

• Examples

How many valence electrons do each of these atoms have?

Mg:Magnesium

Al :.

Aluminum

N :.. .

Nitrogen

Page 35: History of the Atom Scientists and Their Discoveries

Carbon

4 valence electrons

Oxygen

6 valence electrons

Beryllium

2 valence electrons

Counting Valence Electrons

+

+++

+++ --

-

-

++

-

-

--

+

+

++

-

-

++

-

-

--

+

+

++

-

-

+

++

+

+++

+++

-

-

-

-

--

-

-+

Page 36: History of the Atom Scientists and Their Discoveries

Check for Understanding How Many Valence

Electrons?• Hydrogen

• Potassium

• Neon

• Sulfur

• Calcium

1 Valence Electron

1 Valence Electron

8 Valence Electrons

6 Valence Electrons

2 Valence Electrons

Page 37: History of the Atom Scientists and Their Discoveries

Making an Electron Dot Diagram

Element “X” has 8 valence electrons

X. X : X :.

X :..

X :.. . X :

. .. . X :

. .: . X :

. .:. .

Write down the element’s symbol and place the first two dots on

any side of the symbol.

Place the rest of the dots in either a clockwise or counter clockwise manner

around the symbol, with no side receiving two dots

until each side gets one.

If this were an atom of an elementfrom group 1, you would just place theone dot on any side of the element.

Page 38: History of the Atom Scientists and Their Discoveries

Check for Understanding

H

Mg

O

Ne

How many valence electrons does

each atom have?

1 Valence Electron 6 Valence Electrons

8 Valence Electrons 2 Valence Electrons

Page 39: History of the Atom Scientists and Their Discoveries

Symbol = O2+

Ion

• Charged particle that typically results from a loss or gain of electrons

• Two types:– Anion =

negatively charged particle

– Cation = positively charged particle

+

++

+

+++

-

-

-

-

--

-

-+

-

Now that this atom of oxygen just gained an electron, it is no longer

neutral or an atom. It is now considered an ion (anion). This ion has more electrons (9) than

protons (8).

+

-

= 8

= 8

= 896

Symbol = O1-

Now that three electrons were lost, the number of electrons (6)

and protons (8) is still unbalanced; therefore, it is still an ion, but now it is specifically

referred to as a cation.

Currently, this atom of oxygen is neutral because it has an

equal number of electrons (8) and protons (8). Symbol = O

Page 40: History of the Atom Scientists and Their Discoveries

Building Ions

Ions Protons Neutrons Electrons

Carbon (C³¯) 6 6 9

Hydrogen (H¹+)

1 0 0

Oxygen (O²¯) 8 8 10

Lithium (Li³+) 3 4 0

Sodium (Na¹¯) 11 12 12Be aware that the atomic and atomic mass are not

impacted by the loss or gain of electrons.

Page 41: History of the Atom Scientists and Their Discoveries

Isotopes

• Isotopes- atoms that have the same number of protons, but have different numbers of neutrons

• Examples

+

-

+

-

+

-

Hydrogen (Protium) Hydrogen (Deuterium) Hydrogen (Tritium)

Notice that each of these atoms have one proton; therefore they are all types of

hydrogen. They just have a different atomic mass

Page 42: History of the Atom Scientists and Their Discoveries

Isotopes• Recall that the atomic mass is the number of

neutrons and protons in an atom• Example

+

-

+

-

+ -

Hydrogen (Protium)Atomic mass # = 1 amu

Hydrogen (Deuterium)Atomic mass # = 2 amu

Hydrogen (Tritium)Atomic mass # = 3 amu

Page 43: History of the Atom Scientists and Their Discoveries

FORCES IN THE ATOM

• Gravitational Force• Electromagnetic Force

• Strong Force• Weak Force

Page 44: History of the Atom Scientists and Their Discoveries

Gravitational Force

• The force of attraction of objects due to their masses

• The amount of gravity between objects depends on their masses and the distance between them

Do you think this force plays a significantrole in holding the atom together?

Page 45: History of the Atom Scientists and Their Discoveries

Electromagnetic Force

• The force that results from the repulsion of like charges and the attraction of opposites

• The force that holds the electrons around the nucleus

-

+

+

+

--

Notice how the particles with the

same charge move apart and the particles with

different charges move together.

Why are neutrons not pictured above?

Page 46: History of the Atom Scientists and Their Discoveries

Strong Force

• The force that holds the atomic nucleus together

• The force that counteracts the electromagnetic force

• This force is only This force is only strong if the protons strong if the protons and neutrons are and neutrons are close togetherclose together

++

++

Notice how the electromagnetic force

causes the protons to repel each other but, the strong force holds them together.

Would an atom have a nucleus if the strong force did not exist?

Page 47: History of the Atom Scientists and Their Discoveries

-n

Weak Force

• Plays a key role in the possible change of sub-atomic particles.– For example, a neutron

can change into a proton(+) and an electron(-)

• The force responsible for radioactive decay.– Radioactive decay-

process in which the nucleus of a radioactive (unstable) atom releases nuclear radiation.

+

If you need help remembering

weak force, just think of…

Notice how the original particle changes to

something new.

Page 48: History of the Atom Scientists and Their Discoveries

Atoms Forces and Elements

• Forces video

Page 49: History of the Atom Scientists and Their Discoveries

The Periodic Table of Elements

118

Uuo117

Uus116Uuh(292)

115

Uup(288)

114

Uuq(289)

113

Uut(284)

112Uub(285)

111

Rg(272)

110

Ds(269)

109

Mt(268)

108

Hs(269)

107

Bh(264)

106

Sg(266)

105

Db(262)

104

Rf(261)

103

Lr(262)

88

Ra(226)

87

Fr(223)

86

Rn(222)

85

At(210)

84

Po(209)

83

Bi208.980

82

Pb207.2

81

Tl204.383

80

Hg200.59

79

Au196.967

78

Pt195.078

77

I r192.217

76

Os190.23

75

Re186.207

74

W183.84

73

Ta180.95

72

Hf178.49

71

Lu174.967

56

Ba137.327

55

Cs132.905

54

Xe131.29

53

I126.904

52

Te127.60

51

Sb121.760

50

Sn118.710

49

I n114.818

48

Cd112.4

47

Ag107.868

46

Pd106.42

45

Rh102.906

44

Ru101.07

43

Tc(98)

42

Mo95.94

41

Nb92.906

40

Zr91.224

39

Y88.906

38

Sr87.62

37

Rb85.468

36

Kr83.80

35

Br79.904

34

Se78.96

33

As74.922

32

Ge72.61

31

Ga69.723

30

Zn65.39

29

Cu63.546

28

Ni58.69

27

Co58.933

26

Fe55.845

25

Mn54.938

24

Cr51.996

23

V50.942

22

Ti47.87

21

Sc44.956

20

Ca40.078

19

K39.098

118

Uuo117

Uus116Uuh(292)

115

Uup(288)

114

Uuq(289)

113

Uut(284)

112Uub(285)

111

Rg(272)

110

Ds(269)

109

Mt(268)

108

Hs(269)

107

Bh(264)

106

Sg(266)

105

Db(262)

104

Rf(261)

103

Lr(262)

88

Ra(226)

87

Fr(223)

86

Rn(222)

85

At(210)

84

Po(209)

83

Bi208.980

82

Pb207.2

81

Tl204.383

80

Hg200.59

79

Au196.967

78

Pt195.078

77

I r192.217

76

Os190.23

75

Re186.207

74

W183.84

73

Ta180.95

72

Hf178.49

71

Lu174.967

56

Ba137.327

55

Cs132.905

54

Xe131.29

53

I126.904

52

Te127.60

51

Sb121.760

50

Sn118.710

49

I n114.818

48

Cd112.4

47

Ag107.868

46

Pd106.42

45

Rh102.906

44

Ru101.07

43

Tc(98)

42

Mo95.94

41

Nb92.906

40

Zr91.224

39

Y88.906

38

Sr87.62

37

Rb85.468

36

Kr83.80

35

Br79.904

34

Se78.96

33

As74.922

32

Ge72.61

31

Ga69.723

30

Zn65.39

29

Cu63.546

28

Ni58.69

27

Co58.933

26

Fe55.845

25

Mn54.938

24

Cr51.996

23

V50.942

22

Ti47.87

21

Sc44.956

20

Ca40.078

19

K39.098

102

No(259)

101

Md(258)

100

Fm(257)

99

Es(252)

98

Cf(251)

97

Bk(247)

96

Cm(247)

95

Am(243)

94

Pu(244)

93

Np(237)

92

U238.029

91

Pa231.036

90

Th232.038

89

Ac(227)

70

Yb173.04

69

Tm168.934

68

Er167.26

67

Ho164.930

66

Dy162.50

65

Tb158.925

64

Gd157.25

63

Eu151.964

62

Sm150.36

61

Pm(145)

60

Nd144.24

59

Pr140.908

58

Ce140.116

57

La138.906

102

No(259)

101

Md(258)

100

Fm(257)

99

Es(252)

98

Cf(251)

97

Bk(247)

96

Cm(247)

95

Am(243)

94

Pu(244)

93

Np(237)

92

U238.029

91

Pa231.036

90

Th232.038

89

Ac(227)

70

Yb173.04

69

Tm168.934

68

Er167.26

67

Ho164.930

66

Dy162.50

65

Tb158.925

64

Gd157.25

63

Eu151.964

62

Sm150.36

61

Pm(145)

60

Nd144.24

59

Pr140.908

58

Ce140.116

57

La138.906

12

Mg24.305

11

Na22.990

4

Be9.012

3

Li6.941

12

Mg24.305

11

Na22.990

4

Be9.012

3

Li6.941

1

H1.008

1

H1.008

2

He4.003

2

He4.003

18

Ar39.948

17

Cl35.453

16

S32.066

15

P30.974

14

Si28.086

13

Al26.982

18

Ar39.948

17

Cl35.453

16

S32.066

15

P30.974

14

Si28.086

13

Al26.982

10

Ne20.180

9

F18.998

8

O15.999

7

N14.007

6

C12.001

5

B10.811

10

Ne20.180

9

F18.998

8

O15.999

7

N14.007

6

C12.001

5

B10.811

1

2

3

4

5

6

7

1

2

3 4 5 6 7 8 9 10 11 12

13 14 15 16 17

18

Lanthanides

Actinides

Page 50: History of the Atom Scientists and Their Discoveries

Periodic Table

• Something “periodic” occurs at regular or generally predictable intervals

• Periodic law - physical and chemical properties of the elements are periodic functions of their atomic numbers

• Periodic Table of Elements – a table of the elements, arranged by atomic number, that shows the patterns in their properties; based on the periodic law

Can you think of anything that is periodic?

Page 51: History of the Atom Scientists and Their Discoveries

Element

• A pure substance made up of one kind of atom that cannot be broken down into simpler substances by physical or chemical means

• 90 occur naturally on earth• 25 were synthesized (made) by

scientists• The Element Song

http://www.privatehand.com/flash/elements.html

Page 52: History of the Atom Scientists and Their Discoveries

Dmitri Mendeleev

• In the 1860’s he devised a periodic table where the elements were ordered by their atomic masses

• He did this by grouping elements together according to their similarities

• Draft of Mendeleev's Periodic Table

Image taken from: http://jscms.jrn.columbia.edu/cns/2006-04-18/fido-luxuriantflowinghair/mendeleev/

Page 53: History of the Atom Scientists and Their Discoveries

Why do you think there are question marks here?Image taken from: http://www.chemsoc.org/networks/learnnet/periodictable/post16/develop/mendeleev.htm

Mendeleev’s Published Periodic Table of Elements

Page 54: History of the Atom Scientists and Their Discoveries

Mendeleev’s Predictions

• Although Mendeleev’s Periodic Table of Elements had missing elements or “gaps,” he was able to predict the characteristics of these missing elements because of Periodic Law.

Date Predicted

1871 Date Discovered

1886

Atomic Mass 72 Atomic Mass 72.6

Density 5.5 g/cm3 Density 5.47 g/cm3

Bonding Power

4 Bonding Power

4

Color Dark Gray Color Grayish White

“Ekasilicon” GermaniumNotice how

Mendeleev’s predictions

(orange column) were very

accurate when compared to Germanium’s

actual characteristics (green column)

Page 55: History of the Atom Scientists and Their Discoveries

Henry Moseley

• In 1914, his work led to a revision of the periodic table by rearranging the elements by their atomic numbers

• He concluded that the number of protons in an atom is its atomic number

Image taken from: http://dewey.library.upenn.edu/sceti/smith/

Page 56: History of the Atom Scientists and Their Discoveries

3 Classes of Elements

118

Uuo117

Uus116Uuh(292)

115

Uup(288)

114

Uuq(289)

113

Uut(284)

112Uub(285)

111

Rg(272)

110

Ds(269)

109

Mt(268)

108

Hs(269)

107

Bh(264)

106

Sg(266)

105

Db(262)

104

Rf(261)

103

Lr(262)

88

Ra(226)

87

Fr(223)

86

Rn(222)

85

At(210)

84

Po(209)

83

Bi208.980

82

Pb207.2

81

Tl204.383

80

Hg200.59

79

Au196.967

78

Pt195.078

77

I r192.217

76

Os190.23

75

Re186.207

74

W183.84

73

Ta180.95

72

Hf178.49

71

Lu174.967

56

Ba137.327

55

Cs132.905

54

Xe131.29

53

I126.904

52

Te127.60

51

Sb121.760

50

Sn118.710

49

I n114.818

48

Cd112.4

47

Ag107.868

46

Pd106.42

45

Rh102.906

44

Ru101.07

43

Tc(98)

42

Mo95.94

41

Nb92.906

40

Zr91.224

39

Y88.906

38

Sr87.62

37

Rb85.468

36

Kr83.80

35

Br79.904

34

Se78.96

33

As74.922

32

Ge72.61

31

Ga69.723

30

Zn65.39

29

Cu63.546

28

Ni58.69

27

Co58.933

26

Fe55.845

25

Mn54.938

24

Cr51.996

23

V50.942

22

Ti47.87

21

Sc44.956

20

Ca40.078

19

K39.098

118

Uuo117

Uus116Uuh(292)

115

Uup(288)

114

Uuq(289)

113

Uut(284)

112Uub(285)

111

Rg(272)

110

Ds(269)

109

Mt(268)

108

Hs(269)

107

Bh(264)

106

Sg(266)

105

Db(262)

104

Rf(261)

103

Lr(262)

88

Ra(226)

87

Fr(223)

86

Rn(222)

85

At(210)

84

Po(209)

83

Bi208.980

82

Pb207.2

81

Tl204.383

80

Hg200.59

79

Au196.967

78

Pt195.078

77

I r192.217

76

Os190.23

75

Re186.207

74

W183.84

73

Ta180.95

72

Hf178.49

71

Lu174.967

56

Ba137.327

55

Cs132.905

54

Xe131.29

53

I126.904

52

Te127.60

51

Sb121.760

50

Sn118.710

49

I n114.818

48

Cd112.4

47

Ag107.868

46

Pd106.42

45

Rh102.906

44

Ru101.07

43

Tc(98)

42

Mo95.94

41

Nb92.906

40

Zr91.224

39

Y88.906

38

Sr87.62

37

Rb85.468

36

Kr83.80

35

Br79.904

34

Se78.96

33

As74.922

32

Ge72.61

31

Ga69.723

30

Zn65.39

29

Cu63.546

28

Ni58.69

27

Co58.933

26

Fe55.845

25

Mn54.938

24

Cr51.996

23

V50.942

22

Ti47.87

21

Sc44.956

20

Ca40.078

19

K39.098

102

No(259)

101

Md(258)

100

Fm(257)

99

Es(252)

98

Cf(251)

97

Bk(247)

96

Cm(247)

95

Am(243)

94

Pu(244)

93

Np(237)

92

U238.029

91

Pa231.036

90

Th232.038

89

Ac(227)

70

Yb173.04

69

Tm168.934

68

Er167.26

67

Ho164.930

66

Dy162.50

65

Tb158.925

64

Gd157.25

63

Eu151.964

62

Sm150.36

61

Pm(145)

60

Nd144.24

59

Pr140.908

58

Ce140.116

57

La138.906

102

No(259)

101

Md(258)

100

Fm(257)

99

Es(252)

98

Cf(251)

97

Bk(247)

96

Cm(247)

95

Am(243)

94

Pu(244)

93

Np(237)

92

U238.029

91

Pa231.036

90

Th232.038

89

Ac(227)

70

Yb173.04

69

Tm168.934

68

Er167.26

67

Ho164.930

66

Dy162.50

65

Tb158.925

64

Gd157.25

63

Eu151.964

62

Sm150.36

61

Pm(145)

60

Nd144.24

59

Pr140.908

58

Ce140.116

57

La138.906

12

Mg24.305

11

Na22.990

4

Be9.012

3

Li6.941

12

Mg24.305

11

Na22.990

4

Be9.012

3

Li6.941

1

H1.008

1

H1.008

2

He4.003

2

He4.003

18

Ar39.948

17

Cl35.453

16

S32.066

15

P30.974

14

Si28.086

13

Al26.982

18

Ar39.948

17

Cl35.453

16

S32.066

15

P30.974

14

Si28.086

13

Al26.982

10

Ne20.180

9

F18.998

8

O15.999

7

N14.007

6

C12.001

5

B10.811

10

Ne20.180

9

F18.998

8

O15.999

7

N14.007

6

C12.001

5

B10.811

1

2

3

4

5

6

7

1

2

3 4 5 6 7 8 9 10 11 12

13 14 15 16 17

18

Lanthanides

Actinides

Class Color

Metal

Non-Metal

Metalloid

Using this as a guide, color code your periodic table to

show the three classes. Start by highlighting the

“zig-zag.”

Page 57: History of the Atom Scientists and Their Discoveries

3 Classes of Elements

Page 58: History of the Atom Scientists and Their Discoveries

Metals

Location • Found on the left of

the zigzag line/staircase on the periodic table (exception Hydrogen)

Chemical Properties• Have few electrons in

their outer energy level, thus lose electrons easilyPhysical Properties

• Ductile, good conductors, malleable, shiny, most are solid @ room temperature

What metal is not a solid@ room temperature?

Image taken from: http://chemistry.about.com/od/periodictableelements/

ig/Element-Photo-Gallery.--98/Sodium.htm

11

Na

22.990

79

Au

196.967

Page 59: History of the Atom Scientists and Their Discoveries

Metals’ Chemical Properties

Notice: only 1 electron in outer

level

Notice: only 2

electrons in outer level

+

++

+

++

+

+++

-

-

-

-

--

-

-+

-

-

-

+

+++ --

-

-

11

Na

22.990

4

Be

9.012

Page 60: History of the Atom Scientists and Their Discoveries

Metals’ Physical Properties

• Good conductor- electrons (electricity) flow easily through the substance

• Malleable- able to be hammered or pressed out of shape without breaking

Page 61: History of the Atom Scientists and Their Discoveries

Non-MetalsLocation

• Most found to the right of the zigzag line/staircase on the periodic tableChemical Properties

• Most have almost full outer energy levels, thus they tend to gain electrons; some have completely full outer levelPhysical Properties

• Not ductile or malleable, not shiny, poor conductors, most are solid, but some are gas at room temperature

Image taken from: http://nobel.scas.bcit.ca/resource/ptable/cl.htm

Image taken from:https://www.dmr.nd.gov/ndgs/rockandmineral/sulfur.asp

16

S32.06

6

17

Cl35.45

3

Page 62: History of the Atom Scientists and Their Discoveries

Non-metals’ Chemical Properties

   

Notice: 7 electrons in outer level – almost full

Notice: 2 electrons in outer level –

FULL

Notice: 6 electrons in outer level – almost full

+

+++

+++

-

-

-

-

--

-

-+

+

+

+

++

+

+++

-

-

-

-

--

-

-

-

++ -

-

9

F18.99

8

8

O15.99

9

2

He

4.003

Page 63: History of the Atom Scientists and Their Discoveries

Metalloids

Location • Border the zigzag

line/staircase on the periodic tableChemical Properties

• Most atoms have ½ (≈) complete set of electrons in outer levelPhysical Properties

• have properties of both metals and non-metals Image taken from:

http://library.thinkquest.org/C0113863/bios.shtml

Image taken from: http://library.thinkquest.org/C0113863/bios.shtml

5

B10.81

1

14

Si28.08

6

Page 64: History of the Atom Scientists and Their Discoveries

Metalloids’ Chemical Properties

                   

Notice: only 3 electrons in outer

level

Notice: only 4 electrons in outer level

+

+

+++

-

-

-

-

-

++

++

++

+

++

+

+++

-

-

-

-

--

-

-+

-

-

-

-

-

-

5

B10.81

1

14

Si28.08

6

Page 65: History of the Atom Scientists and Their Discoveries

Important Features of the Periodic Table

• Period- each horizontal row of elements on the periodic table

FROM LEFT TO RIGHT OR RIGHT TO LEFT

118

Uuo117

Uus116Uuh(292)

115

Uup(288)

114

Uuq(289)

113

Uut(284)

112Uub(285)

111

Rg(272)

110

Ds(269)

109

Mt(268)

108

Hs(269)

107

Bh(264)

106

Sg(266)

105

Db(262)

104

Rf(261)

103

Lr(262)

88

Ra(226)

87

Fr(223)

86

Rn(222)

85

At(210)

84

Po(209)

83

Bi208.980

82

Pb207.2

81

Tl204.383

80

Hg200.59

79

Au196.967

78

Pt195.078

77

I r192.217

76

Os190.23

75

Re186.207

74

W183.84

73

Ta180.95

72

Hf178.49

71

Lu174.967

56

Ba137.327

55

Cs132.905

54

Xe131.29

53

I126.904

52

Te127.60

51

Sb121.760

50

Sn118.710

49

I n114.818

48

Cd112.4

47

Ag107.868

46

Pd106.42

45

Rh102.906

44

Ru101.07

43

Tc(98)

42

Mo95.94

41

Nb92.906

40

Zr91.224

39

Y88.906

38

Sr87.62

37

Rb85.468

36

Kr83.80

35

Br79.904

34

Se78.96

33

As74.922

32

Ge72.61

31

Ga69.723

30

Zn65.39

29

Cu63.546

28

Ni58.69

27

Co58.933

26

Fe55.845

25

Mn54.938

24

Cr51.996

23

V50.942

22

Ti47.87

21

Sc44.956

20

Ca40.078

19

K39.098

118

Uuo117

Uus116Uuh(292)

115

Uup(288)

114

Uuq(289)

113

Uut(284)

112Uub(285)

111

Rg(272)

110

Ds(269)

109

Mt(268)

108

Hs(269)

107

Bh(264)

106

Sg(266)

105

Db(262)

104

Rf(261)

103

Lr(262)

88

Ra(226)

87

Fr(223)

86

Rn(222)

85

At(210)

84

Po(209)

83

Bi208.980

82

Pb207.2

81

Tl204.383

80

Hg200.59

79

Au196.967

78

Pt195.078

77

I r192.217

76

Os190.23

75

Re186.207

74

W183.84

73

Ta180.95

72

Hf178.49

71

Lu174.967

56

Ba137.327

55

Cs132.905

54

Xe131.29

53

I126.904

52

Te127.60

51

Sb121.760

50

Sn118.710

49

I n114.818

48

Cd112.4

47

Ag107.868

46

Pd106.42

45

Rh102.906

44

Ru101.07

43

Tc(98)

42

Mo95.94

41

Nb92.906

40

Zr91.224

39

Y88.906

38

Sr87.62

37

Rb85.468

36

Kr83.80

35

Br79.904

34

Se78.96

33

As74.922

32

Ge72.61

31

Ga69.723

30

Zn65.39

29

Cu63.546

28

Ni58.69

27

Co58.933

26

Fe55.845

25

Mn54.938

24

Cr51.996

23

V50.942

22

Ti47.87

21

Sc44.956

20

Ca40.078

19

K39.098

102

No(259)

101

Md(258)

100

Fm(257)

99

Es(252)

98

Cf(251)

97

Bk(247)

96

Cm(247)

95

Am(243)

94

Pu(244)

93

Np(237)

92

U238.029

91

Pa231.036

90

Th232.038

89

Ac(227)

70

Yb173.04

69

Tm168.934

68

Er167.26

67

Ho164.930

66

Dy162.50

65

Tb158.925

64

Gd157.25

63

Eu151.964

62

Sm150.36

61

Pm(145)

60

Nd144.24

59

Pr140.908

58

Ce140.116

57

La138.906

102

No(259)

101

Md(258)

100

Fm(257)

99

Es(252)

98

Cf(251)

97

Bk(247)

96

Cm(247)

95

Am(243)

94

Pu(244)

93

Np(237)

92

U238.029

91

Pa231.036

90

Th232.038

89

Ac(227)

70

Yb173.04

69

Tm168.934

68

Er167.26

67

Ho164.930

66

Dy162.50

65

Tb158.925

64

Gd157.25

63

Eu151.964

62

Sm150.36

61

Pm(145)

60

Nd144.24

59

Pr140.908

58

Ce140.116

57

La138.906

12

Mg24.305

11

Na22.990

4

Be9.012

3

Li6.941

12

Mg24.305

11

Na22.990

4

Be9.012

3

Li6.941

1

H1.008

1

H1.008

2

He4.003

2

He4.003

18

Ar39.948

17

Cl35.453

16

S32.066

15

P30.974

14

Si28.086

13

Al26.982

18

Ar39.948

17

Cl35.453

16

S32.066

15

P30.974

14

Si28.086

13

Al26.982

10

Ne20.180

9

F18.998

8

O15.999

7

N14.007

6

C12.001

5

B10.811

10

Ne20.180

9

F18.998

8

O15.999

7

N14.007

6

C12.001

5

B10.811

1

2

3

4

5

6

7

1

2

3 4 5 6 7 8 9 10 11 12

13 14 15 16 17

18

Lanthanides

Actinides

How many

periods (rows)are on the

Periodic Table

Of Elements

?

Page 66: History of the Atom Scientists and Their Discoveries

Period (Row) Properties

• Seven periods on a periodic table (numbered from the top down)

• Atomic numbers and atomic masses increase as you move from the left to the right in a period

• All atoms of the elements in the same period have the same number of orbitals/levels

• All atoms of the elements in a specific period have that respective number of orbitals/levels– Example

• Period 1 = 1 orbital• Period 2 = 2 orbitals• Period 3 = 3 orbitals

• Etc…

Page 67: History of the Atom Scientists and Their Discoveries

Examples of Period (Row) elements having the same number of orbitals/levels in their atoms

++

++ --

-

-

+

+++

+++

-

-

-

-

--

-

- +

++

+++

+

+

+++

+++

-

-

-

-

--

-

-+

-

-

-

-

-

-

++

+

+

+++

+++

-

-

-

-

--

-

-+

-

-

-

In what period (row) doyou think

these atoms reside?

In what period (row) doyou think

these atoms reside?

Page 68: History of the Atom Scientists and Their Discoveries

•Group- each column of elements on the periodic table

Important Features of the Periodic Table

FROM TOP TO BOTTOM OR BOTTOM TO THE TOP

118

Uuo117

Uus116Uuh(292)

115

Uup(288)

114

Uuq(289)

113

Uut(284)

112Uub(285)

111

Rg(272)

110

Ds(269)

109

Mt(268)

108

Hs(269)

107

Bh(264)

106

Sg(266)

105

Db(262)

104

Rf(261)

103

Lr(262)

88

Ra(226)

87

Fr(223)

86

Rn(222)

85

At(210)

84

Po(209)

83

Bi208.980

82

Pb207.2

81

Tl204.383

80

Hg200.59

79

Au196.967

78

Pt195.078

77

I r192.217

76

Os190.23

75

Re186.207

74

W183.84

73

Ta180.95

72

Hf178.49

71

Lu174.967

56

Ba137.327

55

Cs132.905

54

Xe131.29

53

I126.904

52

Te127.60

51

Sb121.760

50

Sn118.710

49

I n114.818

48

Cd112.4

47

Ag107.868

46

Pd106.42

45

Rh102.906

44

Ru101.07

43

Tc(98)

42

Mo95.94

41

Nb92.906

40

Zr91.224

39

Y88.906

38

Sr87.62

37

Rb85.468

36

Kr83.80

35

Br79.904

34

Se78.96

33

As74.922

32

Ge72.61

31

Ga69.723

30

Zn65.39

29

Cu63.546

28

Ni58.69

27

Co58.933

26

Fe55.845

25

Mn54.938

24

Cr51.996

23

V50.942

22

Ti47.87

21

Sc44.956

20

Ca40.078

19

K39.098

118

Uuo117

Uus116Uuh(292)

115

Uup(288)

114

Uuq(289)

113

Uut(284)

112Uub(285)

111

Rg(272)

110

Ds(269)

109

Mt(268)

108

Hs(269)

107

Bh(264)

106

Sg(266)

105

Db(262)

104

Rf(261)

103

Lr(262)

88

Ra(226)

87

Fr(223)

86

Rn(222)

85

At(210)

84

Po(209)

83

Bi208.980

82

Pb207.2

81

Tl204.383

80

Hg200.59

79

Au196.967

78

Pt195.078

77

I r192.217

76

Os190.23

75

Re186.207

74

W183.84

73

Ta180.95

72

Hf178.49

71

Lu174.967

56

Ba137.327

55

Cs132.905

54

Xe131.29

53

I126.904

52

Te127.60

51

Sb121.760

50

Sn118.710

49

I n114.818

48

Cd112.4

47

Ag107.868

46

Pd106.42

45

Rh102.906

44

Ru101.07

43

Tc(98)

42

Mo95.94

41

Nb92.906

40

Zr91.224

39

Y88.906

38

Sr87.62

37

Rb85.468

36

Kr83.80

35

Br79.904

34

Se78.96

33

As74.922

32

Ge72.61

31

Ga69.723

30

Zn65.39

29

Cu63.546

28

Ni58.69

27

Co58.933

26

Fe55.845

25

Mn54.938

24

Cr51.996

23

V50.942

22

Ti47.87

21

Sc44.956

20

Ca40.078

19

K39.098

102

No(259)

101

Md(258)

100

Fm(257)

99

Es(252)

98

Cf(251)

97

Bk(247)

96

Cm(247)

95

Am(243)

94

Pu(244)

93

Np(237)

92

U238.029

91

Pa231.036

90

Th232.038

89

Ac(227)

70

Yb173.04

69

Tm168.934

68

Er167.26

67

Ho164.930

66

Dy162.50

65

Tb158.925

64

Gd157.25

63

Eu151.964

62

Sm150.36

61

Pm(145)

60

Nd144.24

59

Pr140.908

58

Ce140.116

57

La138.906

102

No(259)

101

Md(258)

100

Fm(257)

99

Es(252)

98

Cf(251)

97

Bk(247)

96

Cm(247)

95

Am(243)

94

Pu(244)

93

Np(237)

92

U238.029

91

Pa231.036

90

Th232.038

89

Ac(227)

70

Yb173.04

69

Tm168.934

68

Er167.26

67

Ho164.930

66

Dy162.50

65

Tb158.925

64

Gd157.25

63

Eu151.964

62

Sm150.36

61

Pm(145)

60

Nd144.24

59

Pr140.908

58

Ce140.116

57

La138.906

12

Mg24.305

11

Na22.990

4

Be9.012

3

Li6.941

12

Mg24.305

11

Na22.990

4

Be9.012

3

Li6.941

1

H1.008

1

H1.008

2

He4.003

2

He4.003

18

Ar39.948

17

Cl35.453

16

S32.066

15

P30.974

14

Si28.086

13

Al26.982

18

Ar39.948

17

Cl35.453

16

S32.066

15

P30.974

14

Si28.086

13

Al26.982

10

Ne20.180

9

F18.998

8

O15.999

7

N14.007

6

C12.001

5

B10.811

10

Ne20.180

9

F18.998

8

O15.999

7

N14.007

6

C12.001

5

B10.811

1

2

3

4

5

6

7

1

2

3 4 5 6 7 8 9 10 11 12

13 14 15 16 17

18

Lanthanides

Actinides

How many groups (families)

are on the Periodic Table Of Elements?

Page 69: History of the Atom Scientists and Their Discoveries

Group (Family) Properties

• Eighteen groups on the periodic table (numbered from left to right)

• Atomic numbers and atomic masses increase as you move from the top down in a group (family)

• Atoms of elements in the same group have the same number of electrons in the outer orbitals of their atoms (known as valence electrons) – Exceptions:

• Transition elements (3-12) • Helium (actually has 2 valence electrons)

• Elements in groups usually have similar physical and chemical properties

Page 70: History of the Atom Scientists and Their Discoveries

Determining the Number of Valence Electrons by Using the Periodic

Table*Atoms of elements in Groups 1 and 2 have the same number of valence electrons as their group number.

*Atoms of elements in Group 3-12 do not have a general rule relating their valence electrons to their group number. However, they typically have between 1 or 2 valence electrons.

*Atoms of elements in Groups 13-18 have 10 fewer valence electrons than their group number. (Exception - helium atoms have only 2 valence electrons, even though they are in group 18)

Page 71: History of the Atom Scientists and Their Discoveries

Examples of Group Elements with the same # of valence electrons

                          

87

Fr(223)

55

Cs132.905

37

Rb85.468

19

K39.098

11

Na22.990

3

Li6.941

1

H1.008

+

++

+

+++

+++

-

-

-

-

--

-

-+

-

-

-

+

-

+

-

+++

-

-

-

+++

+++

-

-

-

How many electrons do each of these atoms have in their outer

orbital/level?

What group (family) do these elements reside in?

Page 72: History of the Atom Scientists and Their Discoveries

118

Uuo117

Uus116Uuh(292)

115

Uup(288)

114

Uuq(289)

113

Uut(284)

112Uub(285)

111

Rg(272)

110

Ds(269)

109

Mt(268)

108

Hs(269)

107

Bh(264)

106

Sg(266)

105

Db(262)

104

Rf(261)

103

Lr(262)

88

Ra(226)

87

Fr(223)

86

Rn(222)

85

At(210)

84

Po(209)

83

Bi208.980

82

Pb207.2

81

Tl204.383

80

Hg200.59

79

Au196.967

78

Pt195.078

77

I r192.217

76

Os190.23

75

Re186.207

74

W183.84

73

Ta180.95

72

Hf178.49

71

Lu174.967

56

Ba137.327

55

Cs132.905

54

Xe131.29

53

I126.904

52

Te127.60

51

Sb121.760

50

Sn118.710

49

I n114.818

48

Cd112.4

47

Ag107.868

46

Pd106.42

45

Rh102.906

44

Ru101.07

43

Tc(98)

42

Mo95.94

41

Nb92.906

40

Zr91.224

39

Y88.906

38

Sr87.62

37

Rb85.468

36

Kr83.80

35

Br79.904

34

Se78.96

33

As74.922

32

Ge72.61

31

Ga69.723

30

Zn65.39

29

Cu63.546

28

Ni58.69

27

Co58.933

26

Fe55.845

25

Mn54.938

24

Cr51.996

23

V50.942

22

Ti47.87

21

Sc44.956

20

Ca40.078

19

K39.098

118

Uuo117

Uus116Uuh(292)

115

Uup(288)

114

Uuq(289)

113

Uut(284)

112Uub(285)

111

Rg(272)

110

Ds(269)

109

Mt(268)

108

Hs(269)

107

Bh(264)

106

Sg(266)

105

Db(262)

104

Rf(261)

103

Lr(262)

88

Ra(226)

87

Fr(223)

86

Rn(222)

85

At(210)

84

Po(209)

83

Bi208.980

82

Pb207.2

81

Tl204.383

80

Hg200.59

79

Au196.967

78

Pt195.078

77

I r192.217

76

Os190.23

75

Re186.207

74

W183.84

73

Ta180.95

72

Hf178.49

71

Lu174.967

56

Ba137.327

55

Cs132.905

54

Xe131.29

53

I126.904

52

Te127.60

51

Sb121.760

50

Sn118.710

49

I n114.818

48

Cd112.4

47

Ag107.868

46

Pd106.42

45

Rh102.906

44

Ru101.07

43

Tc(98)

42

Mo95.94

41

Nb92.906

40

Zr91.224

39

Y88.906

38

Sr87.62

37

Rb85.468

36

Kr83.80

35

Br79.904

34

Se78.96

33

As74.922

32

Ge72.61

31

Ga69.723

30

Zn65.39

29

Cu63.546

28

Ni58.69

27

Co58.933

26

Fe55.845

25

Mn54.938

24

Cr51.996

23

V50.942

22

Ti47.87

21

Sc44.956

20

Ca40.078

19

K39.098

102

No(259)

101

Md(258)

100

Fm(257)

99

Es(252)

98

Cf(251)

97

Bk(247)

96

Cm(247)

95

Am(243)

94

Pu(244)

93

Np(237)

92

U238.029

91

Pa231.036

90

Th232.038

89

Ac(227)

70

Yb173.04

69

Tm168.934

68

Er167.26

67

Ho164.930

66

Dy162.50

65

Tb158.925

64

Gd157.25

63

Eu151.964

62

Sm150.36

61

Pm(145)

60

Nd144.24

59

Pr140.908

58

Ce140.116

57

La138.906

102

No(259)

101

Md(258)

100

Fm(257)

99

Es(252)

98

Cf(251)

97

Bk(247)

96

Cm(247)

95

Am(243)

94

Pu(244)

93

Np(237)

92

U238.029

91

Pa231.036

90

Th232.038

89

Ac(227)

70

Yb173.04

69

Tm168.934

68

Er167.26

67

Ho164.930

66

Dy162.50

65

Tb158.925

64

Gd157.25

63

Eu151.964

62

Sm150.36

61

Pm(145)

60

Nd144.24

59

Pr140.908

58

Ce140.116

57

La138.906

12

Mg24.305

11

Na22.990

4

Be9.012

3

Li6.941

12

Mg24.305

11

Na22.990

4

Be9.012

3

Li6.941

1

H1.008

1

H1.008

2

He4.003

2

He4.003

18

Ar39.948

17

Cl35.453

16

S32.066

15

P30.974

14

Si28.086

13

Al26.982

18

Ar39.948

17

Cl35.453

16

S32.066

15

P30.974

14

Si28.086

13

Al26.982

10

Ne20.180

9

F18.998

8

O15.999

7

N14.007

6

C12.001

5

B10.811

10

Ne20.180

9

F18.998

8

O15.999

7

N14.007

6

C12.001

5

B10.811

1

2

3

4

5

6

7

1

2

3 4 5 6 7 8 9 10 11 12

13 14 15 16 17

18

Lanthanides

Actinides

Group (Family) NamesAlkali Metals

Alkaline Earth

Metals

Transition Metals

Boron Group

Carbon Group

Nitrogen Group

Oxygen GroupHalogens

Noble Gases

Page 73: History of the Atom Scientists and Their Discoveries

Identify the Element

118

Uuo117

Uus116Uuh(292)

115

Uup(288)

114

Uuq(289)

113

Uut(284)

112Uub(285)

111

Rg(272)

110

Ds(269)

109

Mt(268)

108

Hs(269)

107

Bh(264)

106

Sg(266)

105

Db(262)

104

Rf(261)

103

Lr(262)

88

Ra(226)

87

Fr(223)

86

Rn(222)

85

At(210)

84

Po(209)

83

Bi208.980

82

Pb207.2

81

Tl204.383

80

Hg200.59

79

Au196.967

78

Pt195.078

77

I r192.217

76

Os190.23

75

Re186.207

74

W183.84

73

Ta180.95

72

Hf178.49

71

Lu174.967

56

Ba137.327

55

Cs132.905

54

Xe131.29

53

I126.904

52

Te127.60

51

Sb121.760

50

Sn118.710

49

I n114.818

48

Cd112.4

47

Ag107.868

46

Pd106.42

45

Rh102.906

44

Ru101.07

43

Tc(98)

42

Mo95.94

41

Nb92.906

40

Zr91.224

39

Y88.906

38

Sr87.62

37

Rb85.468

36

Kr83.80

35

Br79.904

34

Se78.96

33

As74.922

32

Ge72.61

31

Ga69.723

30

Zn65.39

29

Cu63.546

28

Ni58.69

27

Co58.933

26

Fe55.845

25

Mn54.938

24

Cr51.996

23

V50.942

22

Ti47.87

21

Sc44.956

20

Ca40.078

19

K39.098

118

Uuo117

Uus116Uuh(292)

115

Uup(288)

114

Uuq(289)

113

Uut(284)

112Uub(285)

111

Rg(272)

110

Ds(269)

109

Mt(268)

108

Hs(269)

107

Bh(264)

106

Sg(266)

105

Db(262)

104

Rf(261)

103

Lr(262)

88

Ra(226)

87

Fr(223)

86

Rn(222)

85

At(210)

84

Po(209)

83

Bi208.980

82

Pb207.2

81

Tl204.383

80

Hg200.59

79

Au196.967

78

Pt195.078

77

I r192.217

76

Os190.23

75

Re186.207

74

W183.84

73

Ta180.95

72

Hf178.49

71

Lu174.967

56

Ba137.327

55

Cs132.905

54

Xe131.29

53

I126.904

52

Te127.60

51

Sb121.760

50

Sn118.710

49

I n114.818

48

Cd112.4

47

Ag107.868

46

Pd106.42

45

Rh102.906

44

Ru101.07

43

Tc(98)

42

Mo95.94

41

Nb92.906

40

Zr91.224

39

Y88.906

38

Sr87.62

37

Rb85.468

36

Kr83.80

35

Br79.904

34

Se78.96

33

As74.922

32

Ge72.61

31

Ga69.723

30

Zn65.39

29

Cu63.546

28

Ni58.69

27

Co58.933

26

Fe55.845

25

Mn54.938

24

Cr51.996

23

V50.942

22

Ti47.87

21

Sc44.956

20

Ca40.078

19

K39.098

102

No(259)

101

Md(258)

100

Fm(257)

99

Es(252)

98

Cf(251)

97

Bk(247)

96

Cm(247)

95

Am(243)

94

Pu(244)

93

Np(237)

92

U238.029

91

Pa231.036

90

Th232.038

89

Ac(227)

70

Yb173.04

69

Tm168.934

68

Er167.26

67

Ho164.930

66

Dy162.50

65

Tb158.925

64

Gd157.25

63

Eu151.964

62

Sm150.36

61

Pm(145)

60

Nd144.24

59

Pr140.908

58

Ce140.116

57

La138.906

102

No(259)

101

Md(258)

100

Fm(257)

99

Es(252)

98

Cf(251)

97

Bk(247)

96

Cm(247)

95

Am(243)

94

Pu(244)

93

Np(237)

92

U238.029

91

Pa231.036

90

Th232.038

89

Ac(227)

70

Yb173.04

69

Tm168.934

68

Er167.26

67

Ho164.930

66

Dy162.50

65

Tb158.925

64

Gd157.25

63

Eu151.964

62

Sm150.36

61

Pm(145)

60

Nd144.24

59

Pr140.908

58

Ce140.116

57

La138.906

12

Mg24.305

11

Na22.990

4

Be9.012

3

Li6.941

12

Mg24.305

11

Na22.990

4

Be9.012

3

Li6.941

1

H1.008

1

H1.008

2

He4.003

2

He4.003

18

Ar39.948

17

Cl35.453

16

S32.066

15

P30.974

14

Si28.086

13

Al26.982

18

Ar39.948

17

Cl35.453

16

S32.066

15

P30.974

14

Si28.086

13

Al26.982

10

Ne20.180

9

F18.998

8

O15.999

7

N14.007

6

C12.001

5

B10.811

10

Ne20.180

9

F18.998

8

O15.999

7

N14.007

6

C12.001

5

B10.811

1

2

3

4

5

6

7

1

2

3 4 5 6 7 8 9 10 11 12

13 14 15 16 17

18

Lanthanides

Actinides

Period 2 – Group 14 Carbon - CPeriod 5 – Group 2 Strontium - SrGroup 17 – Period 6 Astatine - AtGroup 4 – Period 7 Rutherfordium - Rf

Page 74: History of the Atom Scientists and Their Discoveries

Using the Periodic Table• The boxes that make up the periodic table contain a

significant amount of information. To understand this information, it is necessary to refer to the periodic table’s key(s)

Atomic Number (Number of protons)

Element Symbol(Written with a capital letter or a capital followed by a lower case if two letters )

Atomic Mass(Rounded to a whole number, equals the number of protons and neutrons)

8

OOxygen

15.999

Class Color

Metal

Non-Metal

Metalloid

State (@ Room Temp.)

Symbol

ColorSolid

Liquid

Gas

Which class does Oxygen

fall into?

What is Oxygen’s physical state of matter?

Element Name

Page 75: History of the Atom Scientists and Their Discoveries

Compare:HeHFr

Page 76: History of the Atom Scientists and Their Discoveries
Page 77: History of the Atom Scientists and Their Discoveries

Check for Understanding

• What is the smallest atom in regards to mass in the periodic table? Circle it.

• What is the largest atom (in size in atomic radius) in the periodic table? Put a dot by it.

• What is the most massive atom in the periodic table? Put a star by it.

• What is the most metallic element? Put a box around it.

Page 78: History of the Atom Scientists and Their Discoveries

Check for Understanding

• What is the smallest atom in regards to mass in the periodic table? H

• What is the largest atom (in size) in the periodic table? Fr

• What is the most metallic element? Put a box around it. Fr