Which important property did Mendeleev use to classify the elements in his periodic table and did he stick to that?
Answers
" Dmitri Mendeleev a Russian chemist, first developed the periodical table & he fell a law called Mendeleev periodic rule which says that the ""physical & chemical properties of the elements are the cyclic function of their nuclear masses"".On the basis of this law he developed in a Mendeleev periodic table, where he organized the elements in his periodic table arranged by atomic weight or mass. He then arranged the elements in periods and groups in order of their increasing atomic weight. He placed those elements with its similar properties in the same group.
It is said that, he did not stick to this arrangement for long period.
He found out, if the components were prepared rigorously in order of their building atomic weights, then any components did not fit in this scheme of classification.
Therefore, he ignored the order of atomic weights in few cases.
For example, he considered the atomic weight of iodine is lower than that of tellurium.
Still Mendeleev placed the tellurium (in Group VI) ere iodine (in Group VII) just because iodine’s features are so related to fluorine, chlorine, and bromine. "