Chapter 6 periodic table
This presentation is the property of its rightful owner.
Sponsored Links
1 / 36

CHAPTER 6: Periodic Table PowerPoint PPT Presentation


  • 110 Views
  • Uploaded on
  • Presentation posted in: General

CHAPTER 6: Periodic Table. Development of Periodic Table. Mendeleev Contributions – made very first periodic table p.t. arrangement: elements ordered by increasing atomic mass. Development of Periodic Table. 3) Noticed periodic pattern (repetition) in element properties

Download Presentation

CHAPTER 6: Periodic Table

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Chapter 6 periodic table

CHAPTER 6:Periodic Table


Development of periodic table

Development of Periodic Table

  • Mendeleev

  • Contributions – made very first periodic table

  • p.t. arrangement: elements ordered by increasing atomic mass


Development of periodic table1

Development of Periodic Table

3) Noticed periodic pattern (repetition) in element properties

- elements placed in groups w/ similar properties

- Left gaps for substances yet to be discovered


Mendeleev s periodic table 1871

Mendeleev’s Periodic Table (1871)


Chapter 6 periodic table

4) errors: when new elements discovered, several elements on his table didn’t fit right

- had different properties


Moseley

Moseley

  • periodic table arrangement: elements ordered by increasing atomic number

  • Periodic Law – when elements arranged by increasing atomic number, their physical & chemical properties show a periodic pattern


Modern periodic table

Modern Periodic Table

  • Boxes contain:

    • Element name

    • Element symbol

    • Atomic number

    • Atomic mass


Modern periodic table1

Modern Periodic Table

  • Arrangement – increasing atomic number

    a) groups – columns (vertical)

    b) periods – rows (horizontal)


Two divisions of elements

Two Divisions of Elements

  • Main Group Elements – groups 1A, 2A and 13-18A

    (s & p block)


Two division of elements

Two Division Of Elements

  • Transition Elements – group 3-12B elements (d block)


Classifying elements

Classifying Elements

  • Metals

– elements w/ shine

– solid @ room temp

– conducts heat & electricity

– malleable: put into thin wires

– ductile: pound into sheets


Metals

Metals

a) Alkali Metals – group 1A (except H)

- highly reactive, very soft

b) Alkaline Earth Metals – group 2A

- less reactive and denser than alkali metals

c) Transition Metals – d-block (group 3-12B)


Metals1

Metals

d) Inner transition metals – f-block

i) Lanthanide Series – row 1 of f-block

ii) Actinide Series – row 2 of f-block

La

Ac


Nonmetals

Nonmetals

  • Defn - gases or brittle, dull looking solids

    - poor conductors of heat & electricity

    a) Halogens

    b) Noble Gases

- group 17A

- highly reactive

- group 18A

- very unreactive/stable


Metalloids

Metalloids

  • Defn – BORDER THE STAIRSTEP LINE 

- Have similar chem & phys props as both metals

and nonmetals


Chapter 6 periodic table

Alkali metals

Halogens

Noble Gases

Alkaline earth metals

Transition Metals

Lanthanides

Actinides


Organizing elements by electron configuration

Organizing Elements By Electron Configuration

  • Valence Electron – electrons in highest energy level

atoms in same group have similar chemical

props b/c they have same # of valence e-


Valence electrons and period

Valence Electrons And Period

  • The period indicates what energy level the valence electrons are located on

  • Ex: [Ar] 4s2 3d10 4p1

3 Valence e-

on 4th energy

level


Valence electrons and group number

Valence Electrons and Group Number

  • # of valence electrons equals group number (only for main group elements)

  • exception: Helium

(in group 18, but has

2 valence e- only)


Ex problems

Ex Problems

  • Tell the group, period, and block where these elements are located

[Ne] 3s2

[He] 2s2 2p4

[Kr] 5s2 4d105p5

2

group –

period –

block –

group –

period –

block –

16

group –

period –

block –

17

3

2

5

s

p

p


Periodic trends

Periodic Trends

  • There are certain patterns that occur with the elements as you go across and down the periodic table

    which atom is the biggest? smallest?

    which atom is most reactive/least stable?


Atomic radius size

Atomic Radius (size)

  • Defn – distance from center to edge of electron cloud

  • Period Trend – decreases from left to right

    Why?

    increasing # of protons (+ charge) in nucleus has a greater attraction for

    electrons (- charge)


Atomic radius

Atomic Radius

  • Group Trend – increases from top to bottom

    Why?

    electrons occupy higher energy levels and are farther from the nucleus

Period 1

Period 2

Period 3


Atomic radius1

Atomic Radius

  • Summary

decreases

increases


Chapter 6 periodic table

Ion

  • Defn – atom w/ a positive or negative charge

    - atom lost or gained electrons

    - # protons ≠ # electrons


Cation

Cation

  • Defn – positive ion (atom lost e-)

    - more protons than electrons

  • Comparing atom size vs. its cation size

A

A+

atom A

cation of atom A

cations are SMALLER than its original atom


Anion

Anion

  • Defn – negative ion (atom gained e-)

    - more electrons than protons

  • Comparing atom size vs. its anion size

A-

A

atom A

anion of atom A

anions are LARGER than its original atom


Ion summary

Ion Summary

A-

A

A+

<

<

cation

atom

anion


Ionization energy

Ionization Energy

  • Defn – energy required to remove an electron from an atom

  • Period trend – IE increases from left to right

    Why?

    increased nucleus charge has greater hold on valence e-


Ionization energy1

Ionization Energy

  • Group Trend – IE decreases from top to bottom

    Why?

    atomic size increases, valence e- are farther away so easier to remove (less energy required)


Chapter 6 periodic table

Period 1

Period 2

Period 3


Ionization energy2

Ionization Energy

  • Summary

increases

decreases


Ex problem

Ex problem

  • Rank these atoms from increasing to decreasing ionization energy: Ba, Cs, Cl

increases

decreases

Cl

Cs

Ba

Cl > Ba > Cs


Electronegativity

Electronegativity

  • Defn – relative ability of an atom to attract electrons in a chemical bond

    “how badly does atom want electrons” while in a bond

  • Period Trend – increases from left to right

  • Group Trend – decreases from top to bottom


Electronegativity1

Electronegativity

  • Summary

increases

decreases


Ex problem1

Ex problem

  • Rank these atoms from high to low electronegativity: O, Sr, Mg

increases

decreases

Mg

O

Sr

O > Mg > Sr


  • Login