Headings Alkali Metals Search Questions 
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The Alkali Metals - Group Trends.
As you go down group 1 from lithium to francium, the alkali metals
1) Have bigger atoms.
Each successive element has an extra electron shell.
It is the electron shells which take
up nearly all the
space of an atom.
2) Are more reactive.
As the size of the atoms increase,
the outer electron (which it wants to
lose to become a stable ion)
is further and further from the positive nucleus.
It is the attraction between the negative outer electron and
the positive nucleus which determines how
easily the electron will be
lost.
The bigger the atom, the further
away the outer electron
is,
the more easily the outer
electron is lost, and the
more reactive the metal
is.
Also, the inner electrons (being negatively charged)
protect the outer one from the full attraction of
the positive nucleus.
The outer electron is said to be
shielded by the inner electrons.
The more electron shells there are, the greater the shielding.
3) Are softer, with lower melting and boiling points.
4) Have a higher density.
Headings Alkali Metals Search Questions
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