Question

Mendeleev's periodic table also suffered from a lot of defects. Answer the following questions in keeping in mind the defects of Mendeleev's periodic table.

Which two chemically similar elements were separated?

Answer 1

• In Mendeleev's periodic table, elements were arranged based on increasing atomic mass.
• During Mendeleev's periodic table, only 63 elements were known so after studying the properties of elements he arranged them into vertical columns called groups and horizontal rows called periods.
• Elements that are chemically similar such as gold $\left(\mathrm{Au}\right)$ and platinum $\left(\mathrm{Pt}\right)$ have been placed in separate groups in order to make a periodic table.