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The modern periodic table
CHEMISTRY - Secondary 2
In This part we will study
The elements blocks of the modern periodic table:
• The table is divided into four main blocks, these blocks are :
 s-block.
 p-block.
 d-block.
 f-block.

 s-block elements
• They are placed in the left hand block of the table.

• The s-block contains the elements whose outermost electrons occupy the "s" sublevel.

• The s-block consists of two groups of elements, they are:
- 1A whose electronic configuration ends with ns1
- 2A whose electronic configuration ends with ns2

• Where "n" is the number of the outermost energy level as well as the number of the period at the same time.

 p-block elements
• They occupy the right hand block of the table .

• The p-block contains the elements whose outermost electrons occupy the "p" sublevel, (except helium).

• The p-block consists of six groups, characterized by symbol "A" except "group zero", as follows:

 d-block elements
• They occupy the middle block of the table.
• The d-block contains the elements with the outermost electrons occupy the "d" sublevel.
• The d-block consists of "10"vertical columns representing "8"groups which are characterized by the symbol "B"except eighth group (VIII) which consists of "3"vertical columns.
• The d-block elements are classified according to the number of the outermost energy level and the period number into three series which are:

 The first transition series:
• It includes the elements in which the "3d" sublevel is filled successively.
• It lies in the fourth period and includes the elements from scandium (21Sc) to zinc (30Zn).

 The second transition series:
• It includes the elements in which the "4d" sublevel is filled successively.
• It lies in the fifth period and includes the elements from yttrium (39Y) to cadmium (48Cd).

 The third transition series:
• It includes the elements in which the "5d "sublevel is filled successively.
• It lies in the sixth period and includes the elements from lanthanum (57La) to mercury (80Hg).

 f-block elements
• They are separated down the table, to avoid being too long.
• In which the "f" sublevel is filled successively.
• The f-block is divided into two series - each of them includes "14" elements - which are:

 The lanthanides series:
• It is placed in sixth period, in which the "4f" sublevel is filled successively, it includes 14 elements.
• The elements of this series were named - inaccurately - by rare Earths, because they are quite similar in behavior and very difficult to be separated as the outermost energy level for all of them is 6s2
However, that name isn't accurate, as recently their oxides can be separated by ionic exchange.

 The actinides series:
• It is placed in seventh period, in which the "5f" sublevel is filled successively, it also includes 14 elements.
• All the elements of this series are radioactive and their nuclei are unstable.

Best wishes to you
Mr.Ahmed Elbasha

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