Question

What is the basis of classification of elements in mendeleev's periodic table?

Answer 1

Mendeleev periodic table:

• In Mendeleev, periodic table elements were arranged based on increasing atomic mass and similarity in chemical properties.
• During Mendeleev, only 63 elements were known so after studying the properties of elements he arranged them into vertical columns called groups, and horizontal rows are called periods.
• During the arrangement, there were seven periods and eight groups in Mendeleev's periodic table.
• When Mendeleev made his periodic table, he realized that many elements are not known at that time and were yet to be discovered. So, left gaps in his periodic table for such elements and also predicted their properties.
• Mendeleev gave the prefixes Eka (Sanskrit for “one”), to the elements which were not discovered at that time.
• He named the undiscovered element as eka-boron which was later discovered as Scandium, eka-aluminum was later discovered as Gallium, and eka-silicon was later discovered as Germanium.