Trends%20Review,%20History%20of%20the%20Periodic%20Table,%20Oxidation%20Numbers

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Trends Review, History of the Periodic Table,
Oxidation Numbers
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• Objective
• Today I will be able to
• Apply the trends of ionization energy,
  electronegativity and atomic radius to problem
  solving.
• Explain the history of the periodic table.
• Identify the oxidation numbers for the families
  of elements on the periodic table.
• Evaluation/ Assessment
• Informal assessment Listening to group
  interactions and discussions as they complete the
  analyzing the periodic trends graphing activity
• Formal Assessment Analyzing student responses
  to the exit ticket, graphs and periodicity
  practice
• Common Core Connection
• Build Strong Content Knowledge
• Value Evidence
• Reason abstractly and quantitatively
• Look for and make use of structure

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Lesson Sequence

• Warm Up
• Evaluate Review Chapter 5 worksheet
• Informal assessment
• Elaborate Periodicity Practice
• Formal assessment
• Explain history of the periodic table and
  oxidation numbers

• Elaborate Practice and Exam Review
• Informal Assessment
• Evaluate Exit ticket
• Formal assessment

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Warm - Up

• What is ionization energy?
• How does it change down a family?
• Why does this trend occur?
• How does atomic radius change across a period?
• Why does this trend occur?
• How does an atomic radius compare to an ionic
  radius?

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Objective

• Today I will be able to
• Apply the trends of ionization energy,
  electronegativity and atomic radius to problem
  solving.
• Explain the history of the periodic table.
• Identify the oxidation numbers for the families
  of elements on the periodic table.

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Homework

• Periodic Table (mini-exam) on Thursday and Friday
  next week
• STEM Fair
• Final Research Paper due Monday December 17
• In Class Presentations Wednesday January 23

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Agenda

• Warm Up
• Study guide
• Review Homework
• Periodicity Practice Worksheet
• History of the Periodic Table Notes
• Oxidation Number Notes
• Exam Review
• Exit ticket

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Review HW Chapter 5 Worksheet

• Discuss answers to selected problems and then
  turn in

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Periodicity Practice

• Complete Worksheet and Review as a class

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History of the Periodic Table and Oxidation
Number Notes
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Johann Dobereiner (1829)

• Law of Triads - in triads of elements the middle
  element has properties that are an average of the
  other two members when ordered by the atomic
  weight
• Example - halogen triad composed of chlorine,
  bromine, and iodine

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John Newlands (1864)

• Law of Octaves - states that any given element
  will exhibit analogous behavior to the eighth
  element following it in the periodic table

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Dmitri Mendeleev (1871)

• Developed the first Periodic Table
• He arranged his table so that elements in the
  same column (groups) have similar properties
  increasing atomic mass

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Dmitri Mendeleev (1871)

• Broke the trend of arranging elements solely by
  their atomic mass
• Wanted to keep elements with similar properties
  in the same columns
• Left gaps in his early tables predicted elements
  that had not been discovered would fill in those
  gaps
• - Ekasilicon ? Germanium
• - Germanium was discovered in 1886

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Dmitri Mendeleev (1871)
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Henry Moseley (1913)

• Found a relationship between an elements X-ray
  wavelength and its atomic number (number of
  protons)
• Periodic Law - when elements are arranged in
  order of increasing atomic number, their physical
  and chemical properties show a periodic
  (repeating) pattern
• The periodic law is the basis for arranging
  elements in the periodic table

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Glenn Seaborg

• He reconfigured the periodic table by placing the
  actinide series below the lanthanide series
• Awarded a Nobel Prize in 1951
• Element 106, Seaborgium (Sg), is named in his
  honor

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Oxidation Numbers
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Oxidation Numbers

• Remember, most atoms strive to have eight valence
  electrons (some are satisfied with only two)
• Atoms will form various bonds by gaining, losing,
  or sharing electrons, in order to satisfy the
  Octet Rule

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Oxidation Numbers

• An atoms electron configuration is used to
  determine how many electrons need to be gained,
  lost, or shared
• Example Na (11 electrons)
• 1s2 2s2 2p6 3s1 1 valence electron
• In order for Na to have eight valence electrons,
  would it be easier for it to gain 7 electrons, or
  lose 1?
• Losing 1 is easier

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Oxidation Numbers

• When Na loses an electron it becomes an Na1 ion
• 1s2 2s2 2p6 3s1 becomes
• 1s2 2s2 2p6 8 valence electrons
• Na carries a 1 charge because it has lost an
  electron, and it now has more positively charged
  protons than negatively charged electrons

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Oxidation Numbers

• Another Example Fluorine (9 electrons)
• 1s2 2s2 2p5 7 valence electrons
• In order for F to have eight valence electrons,
  would it be easier for it to gain 1 electron, or
  lose 7?
• Gaining 1 is easier

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Oxidation Numbers

• When F gains an electron it becomes an F-1 ion
• 1s2 2s2 2p5 becomes
• 1s2 2s2 2p6 8 valence electrons
• F carries a -1 charge because it has gained an
  electron, and it now has more negatively charged
  electrons than positively charged protons

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Oxidation Numbers

• There is a fairly consistent pattern to oxidation
  numbers with families
• Transition Metals and Inner Transition Metals
  usually have a varying number of valence
  electrons
• Some dont Zn2, Cd2, Sc2, Ag1

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Exam Review

• Complete with the people in your row. If you have
  questions please ask Ms. Ose

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Exit Ticket

• Which element is more likely to have a higher
  (more negative) electron affinity, Aluminum or
  Sulfur?
• List the oxidation number for the following
  families
• Alkali metals
• Alkaline earth metals
• Halogens
• Noble Gases