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Dobereiner’s law of Triads
Dobereiner’s law of Triads
A German chemist Johann Wolfgang Döbereiner (1829) noted that there were groups of elements with three elements known as triads in each group with similar chemical properties. He tried to give a relationship between the properties of elments and their atomic weights.
Döbereiner stated that when elements with similar properties are taken three at a time and arranged in the ascending order of their atomic weights, the atomic weight of the middle element is the average of the atomic weights of the first and third elements. This statement is called the Dobereiner’s law of triads.
In the first row you will find that atomic weight of sodium (Na) is equal to the average of relative atomic weight of Li and K.
Find average atomic weights of the first and third elements in each row and compare it with the atomic weight of the middle element.
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