Transcript Unit 4: Periodic Trends PPT

Periodic Table
Trends and Similarities
Trends of the Periodic Table:
At the conclusion of our time
together, you should be able to:
1. Give a trend across and down the Periodic
Table for metallic characteristics, reactivity,
atomic radius and ion radius, electron affinity,
ionization energy, and electronegativity.
2. Pick the element with the higher trend above
from a list of several elements
Trends In The Periodic Table:
Ionization Energy
Atomic Radius
Electron Affinity
Electronegativity, Etc.
Atomic Radius Trends – Page
13
Left to Right: Decreases
Top to Bottom: Increases
Ionization Energy Trends –
Page 13
Left to Right: Increases
Top to Bottom: Decreases
Electronegativity Trends –
Page 13
Left to Right: Increases
Top to Bottom: Decreases
Electron Affinity – Page 13
(Add to Page 13)
Left to Right: Increases
Top to Bottom: Decreases
Atomic Radius – Page 14
½ the distance between the nuclei of two
identical atoms that are bonded together.
Trends Explanation – Page 14
Electron-electron repulsion makes radius
larger, very weak interactions.
1.
Proton – electron attraction = smaller
atom
2.

Explains all trends going across a period
Energy level, n (distance from the
nucleus), as they go higher = larger
atom
3.

Explains all trends going down a group
Ionization Energy – Page 14

The energy (effort) required to
remove one electron from a neutral
atom.

Left to Right: Increases


The closer to the nucleus, the harder to take an
electron away.
Top to Bottom: Decreases

The farther away from the nucleus the easier it
is to take an electron away.
Electronegativity – Page 14
A measurement of the ability of an atom in a
chemical compound to attract electrons.
(how strongly an atom holds onto its own
electrons and how strongly it needs another
electron)
 Most electronegative element – Fluorine (F)
Electron Affinity – Page 14
The energy change that occurs when a neutral
atom acquires an electron.
Energy is released from the atom.
Atoms that really want another electron tend to
release more energy.
Ionic Radius Trends – Page 15
Less e repulsion =
smaller radius
More e repulsion =
larger radius
Reactivity Trends
metals ….Francium
nonmetals …Fluorine
Top to Bottom
Left to Right
Increases with
Metals
Decreases with
Nonmetals
Decreases with
Metals
Increases with
Nonmetals
Atomic Radius Trends
Top to Bottom
Left to Right
Increases
(larger size atom)
Decreases
(smaller size
atom)
Ionization Energy Trends
Top to Bottom
Left to Right
Decreases
Increases
Electron Affinity Trends
Top to Bottom
Left to Right
Decreases
(less energy
released)
Increases
(more energy
released)
Noble Gases = 0
Electronegativity Trends
Top to Bottom
Left to Right
Decreases
Increases
Metallic Character
1.
2.
3.
4.
5.
Low ionization energy
Low electronegativities
High luster – shiny
Good conductor or electricity and heat
Malleable and ductile
Most metallic element = Francium
Non Metallic Character
1.
2.
3.
4.
5.
High ionization energy
High electronegativities
Little or no metallic luster
Poor electrical and thermal conductors
Fewer solids
Most nonmetallic element = Fluorine
Metalloid Character
1. Characteristics of both metals and
nonmetals
2. Electronegativities between those of
metals and nonmetals
3. Ionization energies between those of
metals and nonmetals.
4. Boiling pts, Melting pts and Densities
vary widely