Chemistry (NTSE/Olympiad)  

7. Periodic Classification of Element

Early Attempts of Classification

Early attempts of classification
Lavoisier's Classification :
Lavoisier classified elements into metals and nonmetals. This classification was based on certain distinctive physical properties such as hardness, malleability and luster. On the basis of these properties, sodium and lead were classed together as belonging to the group of metals.
(1) Hardness, malleability and luster were found to be the only common properties of sodium and lead, otherwise the two elements were entirely different.
(2) In such a classification there was no place for elements with properties resembling those of metals as well as nonmetals.
There fore, Lavoisier's classification was found to be inadequate.


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