Besides gallium, which other elements have since been discovered that were left by Mendeleev in his Periodic Table? (Any two) Solution:...

Use Mendeleev’s Periodic Table to predict the formulae for the oxides of the following elements: K, C, AI, Si, Ba. Solution: K- K2O...

Solution: (i) They were not applicable for very low mass or very high mass elements. (ii) All the elements couldn’t fit into Dobereiner’s...

Solution: Dobereiner’s triads did exist in the columns of Newlands’ Octaves; For example, the elements Lithium (Li), Potassium (K) and...