Question

State Dobereiners’s law of traids.

Answer 1

Accorsimg to doberneir he arranged the elements in triads in increaing of order of atomic mass.He observed that the mass of middle element was roughly equal to the mean atomic mass of two elements.

Answer 2

According to Dobereiner's law of triads ---
When elements are arranged in order of increasing atomic masses, group of three elements known as triads , having similar chemical properties are obtained.

The atomic mass of middle element of the triad being equal to the arithmetic mean of the atomic mass of other two elements.