The Periodic Table of Elements

Period 3 and Group 16

Created By: Emily Benes & Ashlyn Singer Trout-4th

Intro Video

Groups and Periods Song - The Periodic Table - New Mr. Edmonds 3/4/12 ** Rock to an oldie!


Period 3 is the third row down and reads Sodium, Magnesium, Aluminum, Silicon, Phosphorous, Sulfur, Chlorine, and Argon from left to right.

Group 16 is the sixteenth column on the Periodic Table. It reads Oxygen, Sulfur, Selenium, Tellurium, and Polonium going down.

Period 3

Trends in Period 3

Metals, Nonmetals and Metalloids

  • Period 3: Metals-Sodium, Magnesium, & Aluminum; Nonmetals-Phosphorus, Sulfur, Chlorine, and Argon; Metalloids-Silicon

Group 16

Chalcogen's and Noble Gases

Metals, Nonmetals and Metalloids

  • Group 16: Metals- Polonium; Nonmentals- Oxygen, Sulfur, and Selenium; Metalloids- Tellurium

Atomic Radii

  • Period 3: The atomic radii decreases from left to right
  • Group 16: As you move down the group, the atomic radius increases

Ionic Radii

  • Period 3: The ionic radii increases from left to right on the period.
  • Group 16: As you move down the group, the ionic radius increases.

Average Atomic Mass

The way to determine the average atomic mass of an element is the # of protons added to the # of neutrons multiplied be the percent of abundance. You do this for each isotope then add them together.

Average Atomic Mass of Magnesium


  • Period 3: For metals:decreases left to right; For nonmetals: increases left to right
  • Group 16: As you go down the group, it decreases


  • Period 3: The electronegativity increases left to right
  • Group 16: The electronegativity decreases as you go down

Ionization Energy

  • Period 3: increases left to right
  • Group 16: decreases as you go down

Valence Electrons

  • Period 3: 1, 2, 3, 4, 5 ,6, 7, and 8 from left to right
  • Group 16: 6 all the way down

Electron Configuration

  • Period 3: 1 “s” and 1 “p”
  • Group 16: it adds 1 “s” level and 1 “p” level between O and S and then after that it adds 1 “s”, 1 “d”, and 1 “p”

Lewis Structure

  • Period 3: valence electrons increases by 1 left to right
  • Group 16: same all the way down (6 valence electrons)


Phosphorus to Iodine=Covalent Bond, Non polar

Bonding Between Group 16 and Period 3

The bonding between these two sections of the Periodic Table are the same as the rest of the table: Ionic Bonds-nonmetal to metal, Covalent Bonds-nonmetal to nonmetal, and Metallic Bonds-metal to metal.


Calcium to Chlorine=Ionic Bond,

State of Matter at Room Temperature

  • Period 3: Solids-Sodium, Magnesium, Aluminum, Silicon, Phosphorus and Sulfur Gases-Chlorine and Argon
  • Group 16: Solids: Polonium, Tellurium Gases:Oxygen, Sulfur, Selenium

Boiling Point

  • Period 3: Increase from sodium to aluminum, then decrease to argon
  • Group 16: increase as you go down

Melting Point

  • Period 3: Increase going from sodium to silicon, then decrease to argon
  • Group 16: increase as you go down