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The Periodic Table

The periodic table is a tabular arrangement of the chemical elements, ordered by their atomic number, electron configuration, and recurring chemical properties, whose structure shows periodic trends. The periodic table is an arrangement of the elements in order of their atomic numbers so that elements with similar properties appear in the same vertical column or group.

Lesson 1 (or “Day 1”) Material
Lesson 2 (or “Day 2”) Material
Lesson 3 (or “Day 3”) Material
Lesson 4 (or “Day 4”) Material

3:15 Introduction to the periodic table

4:24 The genius of Mendeleev’s periodic table – Lou Serico

1:33 periodic table symbol explanation (how to read the symbol)


Compare Contrast and Debate

Kick-Off Debate: The periodic table is an arrangement of the chemical elements and are organized on the basis of their atomic numbers, electron configurations and recurring chemical properties. Elements are presented in order of increasing atomic number. The standard form of the table consists of a grid of elements, with rows called periods and columns called groups.

A scientist (Mendeleev) arranged the elements by atomic mass, corresponding to relative molar mass. (see WikiPedia article). Some have argued there are better ways to display/communicate the Elements. Other argue that the Mendeleev design has been used successfully for many years and there is no compelling reason to use a different design.

  • Position A: Alternative ways to display and communicate the Elements (different from the Mendeleev developed table) should be considered.
  • Position B: The Mendeleev developed table has served science well for many decades and is in no need for modification or change.

Resources Documents and Links

Special Notes and Notices

Instructor Emphasis:

  • Science & Engineering Practice: Engage in scientific argument from evidence.
  • Cross-Cutting Concept: Patterns.
Standards Concepts

The periodic table can be used to identify atomic behaviors/properties and predict the outcome of chemical reactions:

  • Elements are placed on the Periodic Table according to repeating patterns of physical and chemical properties, as well as reactivity patterns.
  • Atomic size decreases going across a period of the table due to increasing nuclear charge. Atomic size increases down a group of elements due to addition of energy levels.
  • Periods on the periodic table are based on the energy levels an atom has.