Periodic Table Properties and Trends

Elements have different properties based on the valence electrons in their atoms.  These valence electrons and properties control how the atoms of that element will react with other elements.

Because the number and position of valence electrons an atom has matches up with its location on the Periodic Table, elements with similar valence electrons will have similar properties and are found in the same groups (up and down columns) on the Periodic Table.  In addition, as you go across each row from left to right and down each column on the Table, the elements show patterns in their properties and behaviors based on where they are located in the Table.

Several important properties of atoms we need to know about are:

1. Atomic Size (Radius)
2. Ionic Size (Radius)
3. Ionization Energy
4. Electronegativity

For each of these properties, you need to know what it means, what pattern it shows on the Periodic Table, and why it shows that pattern (what is going on inside the atom with the electrons to make that happen).  These following pictures and link to a flash animation will help with this understanding.

• Atomic Size (Radius) shown as a line graph.

• Atomic Size (Radius) shown as a bar graph in the Periodic Table.

• Click on this link to go to a Flash animation explaining about atomic properties, how they are related to electrons, and the patterns they show in the Periodic Table.

http://www.mhhe.com/physsci/chemistry/essentialchemistry/flash/atomic4.swf

• All of the properties and their patterns on the Periodic Table.