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Mendeleev's Periodic Table (15 Favorites)

ACTIVITY in Periodic Table. Last updated January 25, 2019.


Summary

In this activity, students will use their knowledge of Periodic Trends to analyze and identify unknown elements and organize them correctly in the Periodic Table.

Grade Level

High school

Objectives

By the end of this activity, students should be able to

  • Arrange known elements according to their properties on the Periodic Table.
  • Identify unknown elements by reviewing their properties of atomic radius, malleability, ability to conduct, electronegativity, and ionization energy and using Periodic Trends to place them correctly in the Periodic Table.

Chemistry Topics

This activity supports students’ understanding of

  • Periodic Table
  • Periodic Trends
  • Atomic Radius
  • Electronegativity
  • Ionization energy
  • Physical Properties

Time

Teacher Preparation: 5 minutes
Lesson: 45 minutes

Materials (per group)

  • Mendeleev Periodic Table Cards
  • Scissors

Teacher Notes

  • The Periodic Table Cards include all of the main block elements (groups 1, 2, 13-18) in the first five periods.  The cards include the following information:
    • Element name
    • Atomic radius
    • Malleability information
    • Conductivity information
    • Electronegativity
    • 1st Ionization energy
  • You will find that 10 of the cards do not include the element name and they are shown as Unknown 1 – Unknown 10. Each student group should be given a set of cards and a pair of scissors. Give students the following instructions:
  1. Cut out the element cards – there are 34 total cards that represent the main block elements (Groups 1, 2, 13-18) in the first five periods.
  2. Arrange the cards that include the element’s name as they are arranged on the Periodic Table. There will be 10 blank spaces when they have completed this step. 
  3. There is a simple Periodic Table included on the student activity sheet.  Do not let them access information from the Internet, textbook, or a more detailed Periodic Table.
  4. They should then review the properties listed on the unknown cards and place the cards in the proper place using their knowledge of periodic trends and metallic properties.
  5. When they have finished they should transfer their results to the activity sheet.
  6. Groups should not communicate with each other.
  • Note: The first three elements in group 13 and 16 do not follow the periodic trends for ionization energy moving across a row because of the way electrons are arranged in their orbitals. The cards for these six elements show the ionization energy as bold with an asterisk:  Ionization Energy = 578* kj/mol. If you do not address this anomaly in class, you may choose to remove groups 13 and 16 from this activity.

  • Two sets of cards have been included with this activity.  One includes the 10 unknown elements. The other includes the names of all 34 elements and can be used as a template to customize this activity to fit the needs of your students.

  • Optional: This activity can be used as a summative assessment.

For the Student

Lesson

Background

Dmitri Mendeleev was a Russian scientist who is widely recognized as the chemist who arranged the Periodic Table with the elements in the order of atomic weight. He observed that when arranged this way there was a “periodicity” of recurring similar properties. Other scientists were working on this same task at the time, but Mendeleev was the only one who left spaces in his table and predicted that new elements would be discovered that had the properties that matched the blanks. Mendeleev wrote everything known about the 60 elements that existed at that time on cards, and used those cards to arrange the elements by atomic weight and properties.

Objective

In this activity, you will use your knowledge of Periodic Trends to identify unknown elements and place them correctly in the Periodic Table.

Materials

  • Mendeleev Periodic Table Cards
  • Scissors

Procedure

  1. Cut out the element cards – there are 34 total cards that represent the main block elements (Groups 1, 2, 13-18) in the first five periods.
  2. Arrange the cards that include the element’s name as they are arranged on the Periodic Table. There will be 10 blank spaces when you have completed this step. You may refer to the Periodic Table below to help with this task.
1 2

No elements from Groups 3-12
13 14 15 16
17
18
1 H 2 He
3 Li 4 Be 5 B 6 C 7 N 8 O 9 F 10 Ne
11 Na 12 Mg 13 Al 14 Si 15 P 16 S
17 Cl 18 Ar
19 K 20 Ca
31 Ga 32 Ge
33 As 34 Se 35 Br 36 Kr
37 Rb 38 Sr 49 In
50 Sn
51 Sb 52 Te
53 I 54 Xe
Unknown Element Name
Period Group
1
2
3
4
5
6
7
8
9
10
  1. Review the properties listed on the unknown cards and place the cards in the proper place using what you know about periodic trends and metallic properties.
  2. When you have finished fill complete the conclusion section below.

Conclusion

Write the identity of the unknown elements in the table below.