Question

chlorine Bromine and iodine form a Doberiner's traid.The atomic mases of chlorine and iodine are 35.5 and 126.9 respectively .Predict the atomic mass of bromine

Answer 1

Let mass is chlorine , bromine and iodine be C,B, and I respectively.
According to the Law of Triads ,
B = (I+C)/2 = (35.5+126.9)/2 = (162.4)/2
= 81.2

Answer 2

Hey there,

According to Johann Wolfgang Dobereiner, elements existed as triads in which the 2nd element's mass is approximately equal to the average mass of the other two elements.

Bromine=Chlorine+Iodine/2
=35.5+126.9/2
=162.4/2
=81.2 amu 

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