Classification of Elements and Periodicity in Properties – Solutions
1) What is the basic theme of organisation in the periodic table?
The main idea of organising the elements in the periodic table is to obtain an orderly arrangement that may enable us to study the properties of elements with ease.
2) Which important property did Mendeleev use to classify the elements in his periodic table and did he stick to that?
Mendeleev used “atomic weight” as the fundamental property to classify the elements in the periodic table.
Except for a few cases, he stuck to his principle of classification. For instance, the placement of iodine and tellurium in his periodic tale. Even though the atomic weight of iodine is lower than that of tellurium, he placed tellurium in the sixth group and iodine in the seventh group along with the elements fluorine, chlorine and bromine because of similarities in their properties.