Periodic Table of the Elements

1
Periodic Table of the Elements
2
Early Development of P.T.

• 1700s about 30 elements identified
• Antoine Lavoisier

Antoine Lavoisier's Traité Élémentaire de Chimie,
1789, as quoted in J. R. Partington's A Short
History of Chemistry (Dover, 1989, ISBN
0486659771).
3
Early 1800s

• J.W. Dobereiner
• Triads (groups of 3)
• Similar Properties
• Mass of middle element was close to the average
  of the other two in the triad.

4
1865

• J.A.R. Newlands
• 62 elements arranged by atomic mass
• Similar Properties with every 8th element
• Law of Octaves

5
1869

• Dmitri Mendeleev 1st periodic table.
• Arranged by atomic mass how one element reacted
  with other elements.
• Left gaps for undiscovered elements.

6
Mendeleevs Periodic Table
7
Henry Moseley 1913

• Determined the nuclear charge of the atom.
• Modified Mendeleevs P.T.
• Arranged elements by increasing atomic number.

8
Modern Periodic Table

• Elements are arranged in order of increasing
  atomic number so that elements with similar
  properties fall in the same column.

9
Periodic Law

• The physical and chemical properties of the
  elements are periodic functions of their atomic
  numbers.
• When elements are arranged in order of increasing
  atomic number, elements with similar properties
  appear at regular intervals.

10
Organizing the Squares

• Metals
• Nonmetals
• Metalloids

• Groups Vertical
• Groups have similar chemical and physical
  properties.
• Periods Horizontal Rows

11
Group Labels

• Representative Elements
• Transition Metals
• Inner Transition Metals Lanthanide Actinide
  Series

12
Group Names

• Alkali Metals
• Alkaline Earth Metals
• Halogens
• Noble Gases

13
Blocks
s-block
d-block

p-block
f-block
14
Electron Configuration

• Valence electrons responsible for properties of
  elements.
• Same groups similar electron configurations
  similar properties

15
Representative elements

• Outermost s p sublevels are only
  partially filled.

8A
1A

• Group tells you how many valence electrons
  there are.

2A
3A
4A
7A
6A
5A

16
s-Block

• Chemically Reactive Metals
• Group 1 Alkali Metals (most reactive) Soft,
  silvery, can be cut with a knife.
• Group 2 Alkali Earth Metals (harder, denser,
  stronger than alkali metals).
• Too reactive to be found in nature as free
  elements.

17
p-block

• Main group elements
• All nonmetals (except H)
• All metalloids
• Halogens most reactive nonmetals.
• Noble Gases - inert

18
Transition Metals

• Outermost s sublevel and nearby d sublevel
  contain electrons.

Transition Metals
19
d-block

• Metals with typical metal properties gold,
  silver, etc.
• Transition elements
• Fairly unreactive
• Some exist in nature as free elements

20
Noble Gases

• Outermost s p sublevels are filled.
• Inert Gases (do not readily react).

21
Hydrogen and Helium

• Hydrogen is unique does not fit in with any
  group.
• Helium fits in best with group 18 because its
  highest energy level is full and it is
  nonreactive or inert.

22
Inner Transition Metals

• Outermost s sublevel and nearby f sublevel
  contain electrons.

Inner Transition Metals
23
f-block

• Lanthanides and Actinides
• Lanthanides shiny metals similar in reactivity
  to alkaline earth metals.
• Actinides all are radioactive