Question

What is mendeleeves classification of elements? Write its achievements and limitations

Answer 1

The physical and chemical properties of elements are periodic functions of their atomic numbers.
Limitations of Mendeleefs periodic table
a. position of hydrogen
b.anomalous pair of elements
c. dissimilar elements placed together
d. some similar elements separaged
e. position of isotopes

Answer 2

Hello there !!
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>>MANDELEEV'S CLASSIFICATION OF ELEMENTS IS :

•Mendeleve’s classified the elements discovered at that time based on the increasing order of their atomic masses in horizontal rows till he got an another element which has same properties to the first element.

 •Then he placed this element below the first element and started the second row of elements. In this way he was able to arrange all elements based on their properties.

•His classification of elements in periodic table was the first to include all the elements known at that time.
•In his periodic table there were blank spaces for elements which were yet to be discovered.
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>>HIS LIMITATIONS WERE :

•Mendeleev could not give the reason for the position of hydrogen.

•Isotopes discovered long after when mendeleev had given his classification.
So, isotpes of all elements posed a challenge.

•Atomic masses do not increase in regular manner in going from one element to next.
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>>HIS ACHIEVEMENTS WERE :

•More number of elements were systematicaly arranged.

•Mendeleev left some gaps in his periodic table and predicted the existence of some elements that had not been discovered by that time.

•Noble gases could be placed in a new group without disturbing the existing order.
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I hope, this will help you!! :)