Question

write note on structure of modern periodic table

Answer 1

Periodic Table: It is the table of chemical elements arranged in order of atomic number such that elements with similar atomic structure appear in the vertical columns.

Answer 2

• 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 eighteenth vertical columns (1 to 18) called groups. the arrangement of period and group result into formation of boxes. atomic numbers are serially indicated in the upper part of these boxes.
• each box represents the place for one element. apart from these seven rows, there are two rows of elements placed separately at the bottom of the periodic table. they are lanthanides and actinides series. there are 118 boxes in the periodic table including the two series that means there are 118 places for elements in the modern periodic table. the formation of a few elements was established experimentally very recently and thereby the modern periodic table is now completely filled with 118 elements.
• on the basis of the electronic configuration the element in the modern periodic are divided into four types; viz. s-block, p-block , d-block and f-block. the s-block constitutes group 1 and 2. the groups 13 to 18 constitute the p-block. groups 3 to 12 constitute the d-block. while the lanthanide and actinide series at the bottom form the f-block. the d-block elements are called transition elements. a zig-zag line is shown i the p-block of the periodic table. this zig-zag line how the three traditional types of elements, i.e. metals, nonmetals, and metalloids. the metalloid elements lie along the border of zig-zag line. all the metals lie on the left side of the zig-zag line while all the nonmetals lie on the right side.