Question

why did mendeleev concentrate on the compounds formed by elemnts with oxygen and hydrogen ?​

Answer 1

Answer:

Mendeleev compared the chemical properties of elements by comparing their compounds. He selected hydrogen and oxygen as they are very reactive and formed compounds with most of elements. Hence he used oxides and hydrides of elements as the basic properties of elements for their classification.

Answer 2

Answer:

Among chemical properties, Mendeleev mainly concentrated on the compounds formed by the elements with hydrogen and oxygen because they are highly reactive and hence formed compounds with almost all the elements.

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