1. Tardigrade
  2. Question
  3. Chemistry
  4. Atomic mass of Cl=35.5u and that of I=127u . According to Dobereiner's triad rule, atomic mass of Br will be u. Round off your answer to the nearest integer.

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Q. Atomic mass of $Cl=35.5u$ and that of $I=127u$ . According to Dobereiner's triad rule, atomic mass of $Br$ will be________ $u.$
Round off your answer to the nearest integer.

NTA AbhyasNTA Abhyas 2022

Solution:

According to Dobereiner, the middle element has an atomic mass almost the average of the other two elements.
Hence, $\frac{35 . 5 + 127}{2}=81.25u$