Question

Reference to the long form of the periodic table fills in the blanks with appropriate words.

The serial number of an element in a Periodic Table is also its ---------.

Answer 1

Modern periodic table:

• The modern periodic table is an arrangement of all the elements known in accordance with their increasing atomic number and recurring chemical properties.
• It is a tabular display of 118 chemical elements which consists of horizontal rows called periods and vertical columns are called groups.
• All elements in a group have the same number of valance electrons, and in period elements have the same number of electron shells.

Atomic number:

• The atomic number of an element is equal to the number of electrons or protons in a neutral atom.
• According to modern periodic law, "The physical and chemical properties of the elements are periodic functions of their atomic numbers”.

So, the serial number of an element in a Periodic Table is also its Atomic number.