PERIODIC TABLEChapter 5

LIKE ALWAYS, START AT THE BEGINNING Until 1750, we only had 17 elements

discovered

1789- Antoine LavoisierGrouped by metals, non-metals, gas, earth

1860’s- Dmitri Mendeleev

THE VERY SCIENTIFIC PROCESS OF MENDELEEV He was a teacher, and

wanted to find a better way to describe the elements

Designed a periodic table in which elements were arranged in order of increasing atomic mass

Periodic -means repeating pattern

THE ARRANGEMENT Element’s Name

Mass

Properties: How they reacted

with Oxygen/Hydrogen

What do the symbols mean and numbers?

THE FINAL ARRANGEMENT Columns: by properties Rows: by mass

Periodic Table:An arrangement of elements in columns,

based on a set of properties that repeat from row to row

HOW MENDELEEV DID IT? He could not have a complete chart

Why? He had blanks, where he knew there

had to be something there but did not known what

EARLY BIRD DOESN’T ALWAYS GET THE WORM He was not the first to create a periodic

table or leave blanks in a tableHe did have the best explanation for it

Why was it the best? It was able to be used to make predictions

People had to fill in those blanks!Ex: Eka-aluminum and Gallium

What does this mean?

OUT WITH THE OLD… Mendeleev developed his table without

knowing there were protons…

From what we studied before why would this have been important?

Today’s periodic table is arranged by atomic number!

PERIODS AND GROUPS Periods (Go from 1 to 7)

Rows of the periodic table (horizontal)(L-R)

GroupsEach column (up-down) on the tableThe elements within a group have similar

properties but not identical

The repeating pattern of chemical and physical properties when atomic number is used to arrange is the periodic law.

FOUR PIECES OF INFORMATION ON THE PERIODIC TABLE Atomic number Element Symbol Element Name

Atomic Mass: Value depends

on average mass of the isotopes and their distribution in nature

ATOMIC MASS Depends on the average of isotopes of an

element. Example: The AM of chlorine is 35.453. How was this determined? How many isotopes does chlorine have? Chlorine -35 and Chlorine -37.

Chlorine -35 is 75.78% Chlorine -37 is 24.22%

The average of these percents is 35.453.

ATOMIC MASS UNIT The unit assigned to the mass of an

element

Too small to use grams since anything we measure contains 1000’s to 1,000,000s of atoms

Atomic Mass Unit (AMU)- based on 1/12th of a carbon atom

HOW TO CLASSIFY ELEMENTS1. Solids, liquids, gases

2. Natural and Synthetic Natural: Forms in nature Synthetic: Man-made element

3. Properties: Metals, Nonmetals, metalloids

METALS Majority of elements on table Good conductors of heat/electricity Most are solid at room temp.

Mercury (Hg) Most are malleable (hammered) and

ductile (can be formed into wire) Some react, some don’t

TRANSITIONAL METALS Still classified as metals but have even

more special properties

Noticeable property: They make very distinctive colors

More on these next chapter…

NONMETALS Properties are opposite of metals Poor conductors Most are gases at room temp. If solid, they are very brittle (fragile) Extremely reactive

METALLOIDS The elements in between metals and

nonmetalsEx: They can be conductive at the right

temperaturesSilicon: Used in Computer Chips

TRENDY ELEMENTS Elements to the left of the dark line are

Metals Elements to the right of the dark line are

Nonmetals

As you go from left to right you go from highest metallic properties to more nonmetallic properties

METALS, NONMETALS, & METALLOIDS

1

2

3

4

5

6

7

Metals

Metalloids

Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 349

Nonmetals

THE PERIODIC TABLE

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

88Y

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

* Lanthanides

Y Actinides

Noblegases

Halogens

Transition metals

Alkalineearth metals

Alk

ali m

etal

s

8 9 10 11 12

13 14 15 16 17

18

Uun

110

Uuu

111

Uub

112

Uuq

113

Uuh

116

Uuo

118

VALENCE ELECTRONS Def: An electron that is in the highest

occupied energy level

Critical when dealing with chemical reactions

Elements in the same group are based off these valence electrons

ALKALI METALS Group on the far right (1A)

List the elements in this group as HW.

Have a single valence electron and are extremely reactive

All elements in this group are metals

Not all have the same amount of reactivity. As you go down the chart, the reactivity increases.

ALKALINE EARTH METALS Group 2A All have 2 valence electrons Harder and higher melting pt. than 1A All metals

Differences in reactivity are shown by how they react with water.

MAGNESIUM Key process in photosynthesis

Process plants go through to take sunlight and turn it into usable energy

Its in the center of chlorophyll

Magnesium is light but strong which makes it good for transporting molecules in the plant cell

Also used for bikes and backpack frames

CALCIUM Bones and teeth strong

Milk!

Calcium CarbonateFound in chalk, coral, limestone, and even

in your toothpaste

Calcium Sulfate: A cast

BORON FAMILY Group 3A Three valence electrons 1 metalloid, 4 metals

Contains Aluminum!Most abundant metal in Earth’s Crust

PRODUCTS MADE IN BORON FAMILY Aluminum

10% is in packagingParts in cars and airplanesWindow framesRecyclable!

Boron: Used in special glassware to not shatter when undergoing quick temp. changes

CARBON FAMILY Group 4A Contains 4 valence electrons 1 nonmetal, 2 metalloid, 2 metals

Important: Life wouldn’t exist without carbon

NITROGEN FAMILY Group 5A 5 Valence Electrons 2 nonmetals, 2 metalloids, 1 metal

Most two important elementsNitrogen and Phosphorus

USES FOR NITROGEN FAMILY Fertilizers: uses nitrogen and

phosphorusWhy?Soil has nutrients (Items needed to survive)Sometimes soil doesn’t have enoughFertilizers gives nutrients to soil so plants

can useWhy plants need: Proteins and DNA

OXYGEN FAMILY Group 6A 6 Valence Electrons 3 nonmetals, 2 metalloids

Oxygen is the most abundant element in the Earth’s crust

OXYGEN Needed by life to release energy

Can be stored as liquid in oxygen tanksNo flammable stuff near them

Ozone: Harmful at ground levelProtects us in the atmosphere

SULFUR One of the 1st elements discovered

Main use: Sulfuric AcidMost produced chemical in US65% of it is used to make fertilizer

HALOGENS Group 7A 7 Valence electrons 4 nonmetals, 1 metalloid

Highly reactive (Top highest)

Different physically, similar chemically

USES OF FLUORINE AND CHLORINE Fluorine

Toothpaste (prevents tooth decay)Cooking spray (non-stick)

ChlorineWashingSterilizing (Killing bacteria)

IODINE Iodine is needed in your body to keep

your thyroid gland workingGland is in charge of reactions in your body

Seafood has Iodine

Fresh fish wasn’t available we made Iodized Salt

NOBLE GASES Group 8A Contains 8 Valence Electrons (He:2) 6 nonmetals

Colorless, Odorless, Not reactive

USES OF NOBLE GASES Used in situations where oxygen and

hydrogen is highly reactive with a substance

Bulbs are filled with these gases because oxygen would react at that temp.