Transcript History of Periodic Table

History of Periodic Table
• Objective
▫ Today I will be able to:
 Analyze how elements are arranged on the periodic table based
on properties
 Explain the history of the periodic table.
 Apply the trends of ionization energy, electronegativity and
atomic radius, electron affinity and ionic radius to problem
solving.
• Evaluation/ Assessment
▫ Informal assessment – Listening to group interactions
and discussions as they activity and complete practice
▫ Formal Assessment – Analyzing student responses to
the exit ticket and practice
• Common Core Connection
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Build Strong Content Knowledge
Value Evidence
Reason abstractly and quantitatively
Look for and make use of structure
Lesson Sequence
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Evaluate: Warm-Up
Engage/Explore: Periodic Table Activity
Explain: History of Periodic Table Notes
Elaborate: Periodic Trends Intro
Evaluate: Exit Ticket
Warm-Up
• Which of the following ions are not likely to
form? Explain your answer based off of the
trends we have discussed this unit.
 Al3+
Al2+
Al5-
Objective
▫ Today I will be able to:
 Analyze how elements are arranged on the periodic
table based on properties
 Explain the history of the periodic table.
 Apply the trends of ionization energy,
electronegativity and atomic radius, electron affinity
and ionic radius to problem solving.
Homework
• STEM Fair Due Friday, November 19
Agenda
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Warm-Up
Periodic Table Activity
History of Periodic Table Notes
Periodic Trends Intro
Exit Ticket
Periodic Table Activity
Recreating the periodic table
Periodic Table Activity Directions
• Work with your row to complete the activity
• Arrange the known elements on the cards into
the order of the periodic table
• Place the unknown’s in their spot based on the
properties of the elements
▫ Hint: you are only working with elements in the s
and p block
Discussion
• What process did you use to arrange your
unknowns on the periodic table?
• Did some properties help determine the
unknowns more than others?
• Were there any exceptions?
Answers
Unknown
Element
1
Mg
2
F
3
Rb
4
Kr
5
S
6
Ge
7
Sb
History of the Periodic Table
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
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
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
Dmitri Mendeleev (1871)
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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
Dmitri Mendeleev (1871)
Henry Moseley (1913)
• 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
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
Introduction to the Periodic
Trends
Atomic Radius
• Distance from the center of an atom to the
outermost edge of the electron cloud
Electronegativity
• The ability to attract electrons in a chemical
bond
Ionization Energy
• Energy needed to remove an electron from an
atom
• High ionization energy means atoms hold their
electrons very tightly
Exit Ticket – Make a prediction
• Which elements do you think would have a
higher ionization energy?
▫ Na or Ne
▫ Mg or Ba