The Periodic Table

1
The Periodic Table

• Method of organization
• 1869Dmitri Mendeleev
• Predicted the properties of elements and
  predicted the discovery of other elements based
  on the trends in the table.
• Mendeleevs table was based on atomic mass.
• Moseley discovered that a more appropriate basis
  was atomic number.
• Periodic LawWhen elements are arranged in order
  of increasing atomic number, their physical and
  chemical properties show a periodic pattern.

2
Periodic Table

• Groups or families
• Periods
• Roman numeral column labels
• IUPAC labels
• Common Names
• Alkali metals
• Alkaline Earth metals
• Halogens
• Noble gases

• Transition Metals
• Inner transition metals
• Lathanides
• Actinides

3
Periodic Table
4
Periodic Table

• Metals
• Luster/shine
• Good conductors of heat and electricity.
• Malleable
• Ductile
• All are solids except for Mercury

• Nonmetals
• No luster
• Poor conductors
• Not malleable or ductile
• Many are gases Bromine is a liquid some are
  solids
• Semimetals or metalloids

5
Electron Configurations

• Valence Electrons
• Using American Column labels
• If elements have the same of valence electrons,
  they will have similar chemical properties.
• Abbreviated electron configurations
• Noble Gas Inner Core

6
S, p, d, and f blocks
7
Periodic Trends

• Properties of elements change in a periodic way
  as you move through the periodic table
• Examples
• Atomic Radiusincreases as you move down a group.
  Decreases as you move from left to right across
  a period.
• WHY?

8
(No Transcript)
9
Periodic Trends

• Ion Size
• Increases as you move down a group.
• Metal atoms tend to become smaller when they form
  ions.
• Nonmetal atoms tend to become larger when they
  form ions.
• WHY??

10
(No Transcript)
11
(No Transcript)
12
Ionization Energy

• Amount of energy needed to remove an electron
  from an atom.
• Decrease as you move down a group.
• Increase as you move from left to right across a
  period.
• WHY???
• Successive Ionization Energies
• Whats the pattern?
• WHY???

13
(No Transcript)
14
(No Transcript)
15
Electron Affinity

• Energy change that occurs when an atom gains an
  electron.
• What do the negative numbers mean?
• Irregular periodic trend.
• Nonmetals usually have a more negative electron
  affinity than do metals.
• Noble gases have very high electron affinities.
• Octet Rule

16
Electron Affinity
17
Electronegativity

• Ability to attract electrons in a chemical bond.
• Increases from left to right across a period.
• Decreases as you move down a group.
• Exclude the noble gases.
• WHY???

18
(No Transcript)
19
Periodic Trends

• DensityIncreases as you move down a group.
  Increases as you move right to left across a
  period.
• Melting and Boiling Points decrease as you move
  down a group and increase as you move across a
  period.