Attempts of Elements Classification | summary

The video tutorial summarizes the evolution of element classification, starting with Mendeleev's periodic table, which arranged elements by atomic weights and properties, but had limitations due to isotopes. Mosely later discovered that atomic numbers, not weights, determine periodicity, leading to the modern periodic table with elements arranged by atomic numbers in groups and periods, including inert gases and lanthanides/actinides.

What was the main contribution of Mendeleyev to the periodic table?

How did Mosely's discovery change the classification of elements?

Explain the significance of atomic numbers in the arrangement of elements.

What are the main features of the modern periodic table?

What are the differences between the groups and periods in the periodic table?