Question

Atomic wt. of $Cl=35.5$ and of $I=127$. According to Doeberiner triad rule atomic wt. of $Br$ will be:

• A. $80.0$
• B. $162.5$
• C. $81.25$
• D. $91.5$

Answer 1

The correct option is C $81.25$

Atomic wt. of Cl = 35.5 and I = 127.

According to Doberiner triad rule:

Br =$\frac{35.5+127}{2}=\frac{162.5}{2}=81.25$

Hence, the correct option is $\text{C}$