Watch both videos then complete and submit the quick tests at the end of this post
The first video deals with the periodic table. Elements in the same group have very similar properties. A good example are the Alkali Earth metals of group 1. When elements have the same outer electron (valence shell) arrangement they tend to have similar properties. The halogens in group 17 are another good example of elements sharing the same outer electron configuration. Group 1 elements are extremely reactive as are group 17 elements.
The second video deals with the transfer of electrons to form ions. It is possible to reverse these reactions and turn ions back into the original elements.
After you have watched both sets of videos attempt the revision exercises on electron arrangement and ion formation. For the first 20 elements in particular thie atoms rect to GAIN LOSE or SHARE electrons to gain the electron arrangement of the nearest inert gas (a full outer shell)
The Periodic Table
Ion formation and the reaction between sodium and chlorine.
Electronic arrangement: Quick test
Ion Formation: Quick test.