Periodic - PowerPoint Presentation

Slide1

Periodic

TableSlide2

Dmitri

Mendeleev organized the known elements into a table called the periodic table.

He organized them by their increasing atomic masses.Slide3

Today we organize the

elements

by their increasing Atomic Number. Slide4

Insert copy of the periodic table.Slide5

Rows on the periodic table are called

periods

. All the elements listed in a row belong to the same period. There are 7 (seven) periods.Slide6

Columns in the periodic table are called

groups

or

families

. All elements in a group have

similar

properties. Slide7

Insert copy of the periodic table.

The columns have been given an Arabic number. The columns are numbered 1 – 18 starting at the left and moving to the right.

Please make sure that your periodic table has them numbered like this.Slide8

The outer most energy level is usually not full or complete

.

Valence electrons are important because they determine how an element will

react

with other substance.

These electrons in the outer energy level are called

Valence

electrons

.

Valence Electrons

Slide9

Group 1 and 2 the number of Valence electrons in the outer energy level will

match the group number

.

Insert picture of periodic table.Slide10

Groups 3 through 12 do not follow any particular rule to determine the number of Valence electrons.

Insert picture of periodic table.Slide11

Group 13 to 18 – The Valence electrons for each of these is the group number less

10. For example Group 14 –

10 = 4 Valence electrons.

Insert picture of periodic table.Slide12

Elements whose atoms gain

, lose or share

electrons are reactive and they combine to form the many compounds we use in our daily lives.Slide13

Elements are categorized as metals, nonmetals or metalloids

.

Metals: An element

that has luster, is

malleable

and ductile

,

and is said to be a good conductor of heat and

electricity

.Slide14

Luster describes the way a surface reflects light…therefore metallic luster would be shiny like a metal object.

Malleable means to be able to press or pound the substance into sheets or different shapes.

What is luster, malleable and ductile?

Ductile means that the substance can be drawn out into thin wires.Slide15

Elements are categorized as metals, nonmetals or metalloids (cont’).

Nonmetals: an element that is usually a

gas

or a

brittle

solid at room temperature. It is a poor conductor of heat and

electricity

.Slide16

Elements are categorized as metals, nonmetals or metalloids (cont’).

Metalloid: an element that

shares

some characteristics or properties with both

metals

and nonmetals.Slide17

Group 1 and 2 Elements:

These elements are so reactive that they are only found combined with other elements in nature.Slide18

3

Li

Lithium

6.941

11

Na

Sodium

22.990

19

K

Potassium

39.098

37

Rb

Rubidium

85.468

55

Cs

Cesium

132.905

87

Fr

Francium

223.020

Group 1:

Alkali

Metals

Soft – can be cut with

a

knife

Shiny and

silver colored

Low

Density (some will even float)

Most

reactive

of the metals

Valence electrons

=

1

Reacts

violently

with water forming a hydrogen gas

Compounds from these are very useful such as NaCl

Slide19

4

Be

Beryllium

9.012

12

Mg

Magnesium

24.305

20

Ca

Calcium

40.078

38

Sr

Strontium

87.62

56

Ba

barium

137.327

88

Ra

Radium

226

Group 2:

Alkaline- Earth

Metals

Very

reactive

but not as reactive as Alkali Metals.

Silver

colored

More

dense

than Group 1 metals

Valence electrons =

2

Useful compounds include: Calcium compounds such as cement, plaster, chalk, and YOU.Slide20
Slide21

Group 3 to 12:

Transition

MetalsDo not lose their

valence

electrons as easily as groups 1 & 2.

Less reactive than

Alkali

and

Alkaline

Earth metals

Shiny

Good conductors

of electricityHigher density and melting points (except mercury) than Group 1 and 2Slide22

Group 3 to 12:

Transition Metals (cont’.)

Lanthanides: The first row underneath the periodic table: Shiny, reactive, many are used in the production of steel.Actinides: The second row underneath the periodic table: These elements are all

radioactive

and unstable.

.

Note: Elements found after 94 (Plutonium) are man made and not found in natureSlide23
Slide24

5

B

Boron

10.811

13

Al

Aluminum

26.982

31

Ga

Gallium

69.723

49

In

Indium

114.818

81

Tl

Thallium

204.383

Group 13:

Boron

Group

Reactive

Valence electrons

=

3

Contains

1

Metalloid and

4

Metals

Solid

at room temperature

Aluminum

is the most abundant in this group and the most common in the Earth’s crustSlide25

6

C

Carbon

12.011

14

Si

Silicon

28.086

32

Ge

Germanium

72.64

50

Sn

Tin

118.710

82

Pb

Lead

207.2

Group 14:

Carbon

Group

Reactivity

varies

in this group depending on the element

Valence electrons =

4

This group contains

2

metals

,

1

nonmetal and

2

metalloids.

Many forms found

uncombined

in nature such as diamonds

Compounds are very useful:

proteins

,

fats, carbohydrates, computer chips.Slide26

7

N

Nitrogen

14.007

15

P

Phosphorous

30.974

33

As

Arsenic

74.922

51

Sb

Antimony

121.760

83

Bi

Bismuth

208.980

Group 15:

Nitrogen

Group

Reactivity

varies

in this group depending on the element

Valence electrons =

5

Group contains

1

metal

,

2

Nonmetals, and

2

metalloids

Phosphorous is very

reactive

and only found in nature

combined

with other elements.

All but

nitrogen

are solid at room temperature.

Nitrogen makes up

78%

of our atmosphere.

Generally

unreactive

.Slide27

8

O

Oxygen

15.999

16

S

Sulfur

32.065

34

Se

Selenium

78.96

52

Te

Tellurium

127.60

84

Po

Polonium

209

Group 16:

Oxygen

Group

More

reactive

than group 15

Valence electrons =

6

Group contains

1

Metals

,

3

Nonmetals and

1

Metalloids

Sulfur is found in nature and is used to make

sulfuric

acid, a very commonly used chemical in industry

.

All but

oxygen

are solid at room temperature

.

Oxygen makes up

21%

of the Earth’s Atmosphere

Oxygen is very

reactive

and combines with many other elements especially metals

Rust

is the result of the oxidation of metal.Slide28

9

F

Fluorine

18.998

17

Cl

Chlorine

35.453

35

Br

Bromine

79.904

53

I

Iodine

126.904

85

At

Astatine

210

Group 17:

Halogen

Group

Very

reactive

Valence electrons =

7

Nonmetal group

Poor

Conductors of electricity and heat

React

violently with alkali metals to form salts

Never found

uncombined

in nature

Atoms of these elements only need to gain 1 electron to fill their outer shell

Chlorine and

Iodine

are both in this group and can be combined to make disinfectants.Slide29

2

He

Helium

4.003

10

Ne

Neon

21.180

18

Ar

Argon

39.948

36

Kr

Krypton

83.80

54

Xe

Xenon

131.293

86

Rn

Radon

222

Group 18:

Noble Gas

Group

Non

-

reactant

Valence electrons =

8

Outermost

energy shell is full

Colorless

,

odorless

gases at room temp.

Under normal conditions they do not

react

with other elements

All found on Earth in very

small

amounts

Argon

is the most common in the group

Their non-reactivity makes them very useful for

light

bulbs, helium for blimps and

weather

balloons

.Slide30

1

H

Hydrogen

1.008

Hydrogen Stands Alone:

Properties do not match the properties of any single group

Valence Electrons =

1

Easily looses that one valence electron

Physical properties are like the

nonmetal

group

Most

abundant element in the Universe

Its reactive nature makes it useful as a fuel for

rockets

.Slide31

Insert picture of periodic table.