Question

Define the periodic table. discuss the structure of the periodic table.

Answer 1

Periodic table: The periodic table is an arrangement of all the elements known to man in accordance with their increasing atomic number and recurring physical and chemical properties.

• They are assorted in a tabular arrangement wherein a row is a period and a column is a group$.$
• Elements are arranged from left to right and top to bottom in the order of their increasing atomic numbers$.$
• Thus$,$ elements in the same group will have the same valence electron configuration and hence, similar chemical properties.
• Whereas$,$ elements in the same period will have an increasing order of valence electrons.
• Therefore$,$ as the energy level of the atom increases, the number of energy sub-levels per energy level increases.
• First 94 elements of the periodic table are naturally occurring, while the rest from $95\mathrm{to}118$ have only been synthesized in laboratories or nuclear reactors.