Periodic Table

11SCI - Chemical Reactions

Finn Le Sueur

2024

Mahi Tuatahi

  1. What element is this?
  2. How are these atoms different?
  3. Why are they all still the same element?
  4. What name can be used to describe these?

The Periodic Table

The periodic table is not just a random order of elements, it has logic and reason! It can be used to predict the structure and properties of elements.

But First, Electron Shells!

  • Electrons exist in shells around the atom.
  • Shell one can take two electrons, and shells two and three can take eight electrons.

Periods

  • A row is called a period.
  • Moving left to right on a period the atomic radius decreases, and the electronegativity increases

Electronegativity: how hard it is to remove an electron (how strongly it is attracted to the nucleus), OR, how strongly it wants to take an electron from another atom.

Groups

  • A column is called a group.
  • A group tends to have similar valence shell electron configurations, while increasing the number of shells as you descend.

Valence: Outermost