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Metallic and nonmetallic property
CHEMISTRY - Secondary 2
In This part we will study:
 Acidic and basic property:
• When an element combines with oxygen forming a compound known as oxide.
• There are three types of element oxides, which are:
A - Acidic oxides. B - Basic oxides. C - Amphoteric oxides.

A- Acidic oxides
• The nonmetallic oxides are named by acidic oxides,
Because:

B- Basic oxides
• The metallic oxides are usually known as basic oxides.
• Some basic oxides are not soluble in water and others are soluble in water forming alkalis, the water soluble basic oxides are also known as alkali oxides.

Amphoteric oxides: are element oxides that react with acids as basic oxides and react with bases as acidic oxides forming in both cases salt and water.The graduation of acidic and basic property in the periodic table

Application
The graduation of acidic and basic property in the third period.
The following figure expresses the graduation of acidic and basic property in the third period.
It is shown that, as the atomic number increases the basic property decreases and the acidic property increases.

Note
 The acidic property of hydrogen compounds of group 17 (halogens) increases as the atomic number increases.
Because the increase in the atomic number in the group leads to the increase in the atomic radius of halogen, therefore its attraction force to hydrogen atom decreases, making it easier to be ionized.

The acidic and basic property of the hydroxy compounds
Oxygenated acids (acids contain oxygen) and bases are considered as hydroxy compounds, they can be represented by the general formula (MOH), where M is the element atom.

The hydroxy compounds can be ionized by either ways:
Note
If the strength of (M - O) bond and the strength of (O - H) bond are equal, the substance will be ionized as an acid or a base depending on the reaction medium, this means that it reacts as a base in the acidic medium and as an acid in the basic medium.

Best wishes to you
Mr.Ahmed Elbasha

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