How to Teach the Periodic Table

Students should be reasonably fluent in the lighter elements of the periodic table, so some memorization should be taught. Mnemonics are available to help. However, most of the emphasis should be on reading and understanding the periodic table's structure.

Difficulty: Moderately Challenging

Instructions

Things You'll Need:

• grid-shaped period table of the elements
• spiral-shaped period table of the elements (optional)

Mnemonics

1. Teach a mnemonic for the first nine elements: Hi, He Lies Because Boron Can Not Oxidize Fluoride.
   
   These stand for the first nine elements in order: hydrogen (H), helium (He), lithium (Li), beryllium (Be), boron (Bo), carbon (C), nitrogen (N), oxygen (O) and fluorine (F).

2. Teach a mnemonic for the next eight elements: New Nation Might Also Sign Peace Security Clause.
   
   These stand for the next eight elements in order: neon (Ne), sodium (Na), magnesium (Mg), aluminum (Al), silicon (Si), phosphorus (P), sulfur (S), and chlorine (Cl). There is of course the risk of mistaking "peace" for potassium, but can be avoided if the students learn that K is its symbol.

3. Teach another mnemonic, for the first 20 elements. Explain that H. Helibebcnof and Nena Mgalsipsclarkca are the two Russian inventors of the periodic table.
   
   Of course, Mendeleev is the Russian inventor of the table that we use today, so this pretense, as well as the complexity of the names may not be a popular choice for teachers.

Gridlike Structure

4. Explain the significance of rows.
   
   Teach that each successive element has an additional proton and electron, and has a complete outer electron shell at the end of the row.

5. Explain the significance of columns.
   
   The columns group elements with similar properties together. For example, columns that are opposite distances from the noble gases form ionic bonds together. The noble gas column should be emphasized.

6. Explain that the nearest distance to the noble gases determines much of the element's chemistry.
   
   This is because the shortest distance to having a full outer shell (i.e. the fewest number of electrons needed to be lost or gained) is what usually determines how an atom binds in a molecule.

7. Explain the variation in row length.
   
   The increasing capacity of the outer shell for each row (2, 8, 8, 18, 18, 32, and 32) explains the differing length of the rows.

8. Teach where the lanthanide (lanthanoid) and actinide (actinoid) series below the grid fit in, in the sixth and seventh rows.
   
   Relate this to the previous lesson, that this is an effort to represent different sizes of outer shell. This is also an opportunity to explain that the names lanthanide and actinide are historical, and being replaced with their -noid counterparts.

9. Explicate the reason for the element placements at the top of grid.
   
   The reason the first three rows are split should be explicitly pointed out, that the point is to center the elements on the noble gases. This can be related to the earlier lesson on the quickest path to a full outer shell.

10. Explain the periodicity of the grid further by presenting a spiral periodic table.
    
    The Chemical Galaxy website sells such spiral representations. Note that such a representation was suggested in Mendeleev's time; this is not a new idea.

References

• Raymond Chang; Chemistry; 1984
• A New Vision of the Periodic Table of the Elements
• Periodic Table Memory Pegs

[ladale]

on 10/19/2009 Charles,

This is a good starting point. I teach and will be taking a refresher course in Chemistry soon, and need to order the book (on the periodic table).
Your method will be useful and helpful along the way.
Nice work -

LADale