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Graduation of representative elements Properties
CHEMISTRY - Secondary 2
In This part we will study:
 Ionization potential (Ionization energy):
If an energy is supplied to an atom, electrons may be excited and transferred to higher energy levels, but if a sufficient energy is supplied, the most loosely bound electron may be completely removed, giving a positive ion.
The minimum amount of this energy is called ionization potential.

Ionization potential (Ionization energy): It is the amount of energy required to remove the most loosely bound electron completely from an isolated gaseous atom.
• The atom of the same element has more than ionization energy as shown in the following:
Application
The first ionization potential of noble gases and alkali metals.

• The first ionization potential of noble gases is very high, due to the stability of their electronic configuration and it is difficult to remove an electron from a completely filled shell.
• The first ionization energy of alkali metals is lower than that of all elements,
Due to the easily loss of the valence electron.

The ionization potentials of magnesium:
The corresponding figure expresses the ionization potentials of magnesium and it's clear that :
• The second ionization energy of magnesium is higher than the first one, due to the increasing of the effective nuclear charge (Zeff).
• The third ionization potential of magnesium is much higher than that of its first and second ones, because it results in the breaking up of a completely filled energy level.

The graduation of ionization potential in the periodic table
Example
In the light of your knowledge for the graduation of ionization potential in the periodic table:

Mention which atom is higher in ionization potential in each of the following pairs of atoms with an explanation for your answer:

Solution
(1) The ionization potential of 16S is higher than that of 13Al, because the ionization potential increases in the same period as we move from left to right by increasing the atomic number.

(2) The ionization potential of 3Li is higher than that of 55Cs, because the ionization potential decreases in the same group as we go down the group by increasing the atomic number.


Best wishes to you
Mr.Ahmed Elbasha

كيمياء الصف الثاني الثانوي لغات - الفصل الدراسي الاول
شرح كيمياء لغات تانية ثانوي - مستر احمد الباشا