How does ionization energy affect reactivity in elements?

[NewChemTeache]

I read this here:

http://chemistry.about.com/od/chemistryglossary/a/ionizationenerg.htm

The higher the ionization energy, the more difficult it is to remove an electron. Therefore, ionization energy is in indicator of reactivity.



So my question is:

How does this explain the high reactivity of the halogens?

- I understand that they will remove electrons from other elements to achieve a noble gas configuration, but that statement above seems to disagree with how the akali metals can have a low ionization energy and be very reactive and the halogens have a very high ionization energy and be very reactive.

Please explain.

Thank you,
Rob

 

[Borek]

Yes, the wording seems to be slightly misleading. Low ionization energy suggests high reactivity, no doubt about it, but high ionization energy not necessarily means non-reactive. Although in most cases it does, as there are many more metals than non-metals in periodic table.