Periodic Table - PowerPoint PPT Presentation

About This Presentation
Title:

Periodic Table

Description:

A property of certain elements, as carbon, sulfur, ... Periodic Table Author: rquackenbush ... Allotropes What is an allotrope? – PowerPoint PPT presentation

Number of Views:59
Avg rating:3.0/5.0
Slides: 46
Provided by: rqua1
Category:

less

Transcript and Presenter's Notes

Title: Periodic Table


1
Periodic Table
  • 1869
  • Dmitri Mendeleev in Russia
  • Lothar Meyer of Germany
  • Published nearly identical schemes

2
Henry Moseley
  • 1913
  • Developed the concept of atomic numbers

3
Groups
  • Vertical Columns
  • Families
  • Elements have similar properties
  • Same number of valence electrons (the number of
    electrons in outer most shell)

4
Periods
  • Horizontal rows
  • Period number corresponds to number of energy
    levels

5
Period   GROUPIA   GROUPIIA Transition Metals Transition Metals Transition Metals Transition Metals Transition Metals Transition Metals Transition Metals Transition Metals Transition Metals Transition Metals GROUPIIIA GROUPIVA GROUPVA GROUPVIA   GROUPVIIA   GROUPVIII (0)
1 2He-
  2 3Li1.0 4Be1.5 5B2.0 6C2.5 7N3.0 8O3.5 9F4.0 10Ne-
3 11Na0.9 12Mg1.2 13Al1.5 14Si1.8 15P2.1 16S2.5 17Cl3.0 18Ar-
4 19K0.8 20Ca1.0 21Sc1.3 22Ti1.5 23V1.6 24Cr1.6 25Mn1.5 26Fe1.8 27Co1.9 28Ni1.9 29Cu1.9 30Zn1.6 31Ga1.6 32Ge1.8 33As2.0 34Se2.4 35Br2.8 36Kr-
5 37Rb0.8 38Sr1.0 39Y1.2 40Zr1.4 41Nb1.6 42Mo1.8 43Tc1.9 44Ru2.2 45Rh2.2 46Pd2.2 47Ag1.9 48Cd1.7 49In1.7 50Sn1.8 51Sb1.9 52Te2.1 53I2.5 54Xe-
6 55Cs0.7 56Ba0.9 57La1.1 72Hf1.3 73Ta1.5 74W1.7 75Re1.9 76Os2.2 77Ir2.2 78Pt2.2 79Au2.4 80Hg1.9 81Tl1.8 82Pb1.9 83Bi1.9 84Po2.0 85At2.2 86Rn-
7 87Fr0.7 88Ra0.9 89Ac1.1 104Rf- 105Ha-
6
Periodic Table
  • Most of the elements are metals
  • Gases H,N,O,F,Cl and Group 18
  • Liquids Hg and Br

7
Metals
  • Left of zig zag line
  • Low ionization energy and electronegativity
  • Lose electrons to form positive ions
  • Metallic luster when polished
  • Good conductor of heat and electricity
  • Malleable (made into sheets)
  • Ductile (made into wire)
  • Most are solid at room Temperature (Hg is a
    liquid)

8
Lower Left of Table
  • Most Metallic Character
  • Most reactive metal
  • YouTube - Brainiac Alkali Metals

9
Nonmetals
  • Right of zig zag line (except group 18 Noble
    gases)
  • Gain electrons to form form negative ions
  • High ionization energy (attraction for electrons)
    and high electronegativity
  • Lack luster and form brittle solids
  • Poor conductors of heat and electricity
  • Exist as gases (mostly) solids (molecular or
    network) bromine is a volatile liquid at room
    temperature.

10
Metalloids
  • Touch zig zag
  • Known as semi-metals
  • At the border of metals and nonmetals
  • Properties are similar to metals and nonmetals
  • Boron, silicon, germanium, arsenic, antimony and
    tellurium

11
Metalloids
12
Group 1 Elements
  • Alkali Metals
  • One valence electron
  • React with acids to product hydrogen gas
  • Form strong bases

13
Group 2 Metals
  • Alkali earth metals
  • 2 valence electrons
  • Form weak bases

14
Metals
  • Reactivity increases as we go down a group
  • Reactivity decreases as we go across a period
    (left to right)
  • Ex. Sodium is more reactive than Magnesium
    (period 3)
  • Why? Sodium wants to give the one electron away
    faster.
  • Group 1 larger atomic size
  • Group 2 greater nuclear charge

15
Group 17
  • Halogens
  • 7 valence electrons
  • Diatomic molecules
  • High electronegativity
  • Very reactive, occurs in nature only as compounds
  • All three phases of matter exist.

16
Phases
  • Fluorine and chlorine are gases
  • Br is a liquid
  • Iodine and astatine are solids

17
Group 18
  • Noble Gases
  • Inert Gases-old name, they were thought to be
    unreactive.
  • Chemically unreactive
  • Completely filled valence shells
  • Monoatomic

18
Groups 3-11
  • Transition elements
  • Positive oxidation states
  • Formed colored compounds
  • d sublevels lose electrons from an inner energy
    level
  • Forms ions of more than one stable charge
  • Ex. Fe2 and Fe3

19
Trends
  • Bottom left most reactive metal
  • Top right (excluding group 18) most reactive
    nonmetal
  • Metals reactivity increases as you go down a
    group
  • Nonmetals reactivity increases as you go up a
    group

20
Ionization Energy
  • Energy needed to remove an electron from an atom
  • The greater the attraction for electrons the more
    energy is needed to remove the electron
  • The smaller the ionization energy, the easier it
    is to remove an electron

21
Ionization Energy
  • Li 520
  • B 801
  • O 1314
  • Ne 2081
  • Trend Ionization Energy increases across a
    period.

22
Ionization Energy
  • C 1086
  • Si 787
  • Ge 762
  • Pb 716
  • Trend Ionization Energy decreases down a group.

23
Electronegativity
  • Is the attraction for electrons. The larger the
    electronegativity the more the atom attracts
    electrons.
  • 3 Factors
  • Nuclear charge - of protons, increase charge
    greater attraction
  • Principal energy level The higher the principal
    energy level of the outermost electrons, the
    greater the distance from the nucleus, the weaker
    is the pull
  • Electron Cloud Effect shields the outermost
    electrons from the nucleus. The inner electrons
    repel outermost electron

24
Electronegativity
  • Li 1.0
  • B 2.0
  • O 3.4
  • Ne -----
  • Why doesnt Ne have an Electronegativity?
  • It is not reactive. Does not react with any
    element.
  • Trend Electronegativity increases across a period.

25
Electronegativity
  • C 2.6
  • Si 1.9
  • Ge 2.0
  • Pb 1.8
  • F 4
  • Cl 3.2
  • Br 3.0
  • I 2.7

26
Electronegativity
  • Trend
  • Electronegativity decreases down a group.

27
Atomic Radius
  • Is half the distance between adjacent nuclei (the
    distance from the nucleus to the outer most
    valence electrons).
  • Size of the atom
  • Related to the attraction of the nucleus for its
    electrons
  • Decreases as the atomic number increase as a
    result of the force of attraction between the
    positive nucleus and the negative electrons.

28
Atomic Radius
  • Li 130
  • B 84
  • O 64
  • Ne 62
  • Trend Atomic Radius decreases across a period.

29
Atomic Radius
  • C 75
  • Si 114
  • Ge 120
  • Pb 145
  • Trend Atomic Radius increases down a group.

30
Ionic Radius
  • Metals lose electrons, ionic radius becomes
    smaller
  • Nonmetals gain electrons, the ionic radius
    becomes larger

31
What do all of these have in common?
32
They are all Carbon.
33
What do all of these have in common?
Graphite
Carbon Fiber Clothes
Artists Charcoal
Carbon Fiber Custom Wheel
Charcoal
Diamond
34
Allotropes
  • Arent we all the same deep down?

35
What is an allotrope?
  • A structurally differentiated form of an element
    that exhibits allotropy.

36
What is allotropy?
  • A property of certain elements, as carbon,
    sulfur, and phosphorus, of existing in two or
    more distinct forms.

37
A.K.A.
  • When an element exists in pure forms that differ
    in the way the atoms are arranged.

38
Buckminsterfullerene
39
(No Transcript)
40
Other Allotropes
  • Sulfur
  • S4, S5, S8
  • Oxygen
  • O2 and O3
  • Phosphorous
  • P4 and P2

41
(No Transcript)
42
(No Transcript)
43
(No Transcript)
44
(No Transcript)
45
(No Transcript)
Write a Comment
User Comments (0)
About PowerShow.com