Question

In which of the following compounds, the oxidation number of iodine is fractional?

• A. $I{F}_7$
• B. $I_3^{-}$
• C. $I{F}_5$
• D. $I{F}_3$

Answer 1

The correct option is B $I_3^{-}$

Oxidation number of Iodine in:

$I{F}_7$: $x+7\times (-1)=0$; $x=7$

$I_3^{-}$: $x\times 3=-1$; $x=-1/3$

$I{F}_5$: $x+5\times (-1)=0$; $x=5$

$I{F}_3$: $x+3\times (-1)=0$; $x=3$

Therefore oxidation number of $I$ is fractional in $I_3^{-}$.Option B is correct.