Question
Question: Write a short note. Structure of the modern periodic table....
Write a short note.
Structure of the modern periodic table.
Solution
Periodic Table is the table of chemical elements arranged in order of atomic number such that elements with similar atomic structures appear in the vertical columns. The modern periodic table is based on the modern periodic law and it is being made by Henry Moseley.
Complete answer:
The modern periodic law states that “Physical and Chemical properties of elements are periodic functions of their atomic number “.
In the modern periodic table, the elements are arranged in the order of their increasing atomic number. In the modern periodic table, there are seven horizontal rows called periods and eighteen vertical columns (1 to 18) called groups. The arrangement of the periods and groups results in formation of boxes.
Group number | Group name | Property |
---|---|---|
Group 1 | Alkali metals | They form strong alkalis with water |
Group 2 | Alkaline earth metals | They also form alkalis but weaker than group 1 elements |
Group 13 | Boron family | Boron is the first member of this family |
Group 14 | Carbon family | Carbon is the first member of this property |
Group 15 | Nitrogen family | This group has nonmetals and metalloids |
Group 16 | Oxygen family | They are also known as halogens |
Group 17 | Halogen family | The elements of this group form salts. |
Group 18 | Zero group | They are noble gases and under normal conditions they are inert. |
Note:
Although it’s being used, it has some shortcomings like it doesn’t have a fixed place for Lanthanide and Actinide. It comprises elements arranged in periods and groups. Where the elements in the group have the same valence electrons and increase in number of shells by one. And in periods there is the same number of shells and the valence electrons increase by one.