Did Dobereiner's triads also exist in the columns of Newland's Octaves? Compare and find out.

Lithium, sodium and potassium elements were put in one group on the basis of their similar properties. What are those similar properties.

(a) What was Mendeleev's basis for classification of elements?

(b) Mendeleev's contributions to the concept of a periodic table laid the foundation for the Modern Periodic Table. Give reasons.

State Mendeleev's periodic law.