Group 1 - Alkali Metals

How does the reactivity of the alkali metals change down the group and why?

Reactivity increased down the group

Because the outer electron is further from the nucleus

So there is more shielding by full inner shells

Therefore the attraction for the outer electron is less (more easily lost)

How does the melting point and boiling point of the alkali metals change down the group?

It decreases

Properties of alkali metals:

Low density - float on water

Easily cut

Shiny when freshly cut (oxide layer)

React with non metals to form ionic compounds

Why are alkali metals stored in oil?

To prevent reaction with oxygen and water