Class: XChapter Name: Periodic classification of elements
Dobereiner’s triads: Johann Wolfgang Dobereiner, a German chemist, classified the known elements in groups of three elements on the basis of similarities in their properties. These groups were called triads.
Characteristic of Dobereiner’s Triads:
a. Properties of elements in each triad were similar.
b. Atomic mass of the middle elements was roughly the average of the
atomic masses of the other two elements.