Question

how much elements that was found in the period of doberiner.

Answer 1

33 elements

Ans: During the time of classification elements by Dobereiner there were very few elements (less than 33 elements) discovered. Later as more number of elements were discovered the theory has proven draw backs.

Answer 2

$\underline{\underline{\Huge\mathfrak{Answer}}}$

There are 33 elements watch found in the period of Doneriner. No doubt, the traids given by the Doneriner were helpful in grouping some elements with similar characteristics together, but he could not arrange all the elements known at that time into traids.