C9 Periodic Trends

Objectives covered in this topic page are outlined in the C9 The Periodic Table area of the Specification

Valance Electrons - Group 1

To repeat a fact we learned when arranging electrons - the number of electrons in the outer shell dictates the Group Number in the periodic table.

Hence - Neutral atoms with one valance electron in their outer shell are all from Group 1

This can be observed in the Electron Arrangement of all Group 1 metals

Another Trend you can observe from the above graphic is how the Size of the atom increases as you go down the group.

When you add another Shell to atoms the distance from the Nucleus to the outer shell increases (this is called the atomic radius).

Reactivity

As you descend down Group 1 the metals become MORE REACTIVE.

This is usually displayed in the classroom when observing Group 1 metals react with Water