How do you determine first ionization energy? Can you tell by looking at the periodic table?

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1 Answer
anor277
Jun 27, 2016

How else but by experiment?

Explanation:

The first ionization energy is determined by the energy of the following reaction:

#E(g) + Delta rarr E^+(g) + e^-#

Ionization energies INCREASE across a Period (from left to right as you face the table), and DECREASE down a Group. The rationalization behind this phenomenon underlies our ideas regarding Periodicity.

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