Question

An oxide of iodine (atomic mass = $127$) contains $25.4\, g$ of iodine and $8\, g$ of oxygen. Its formula would be

• A. $I _{2} O _{3}$
• B. $I _{2} O$
• C. $I _{2} O _{5}$
• D. $I _{2} O _{7}$

Answer 1

Answer: (C)

$25.4\, g\, I _{2}$ combines with $8\, g$ of oxygen.
$\therefore 254\, g$ iodine will combine with $80\, g$ of oxygen.
$\therefore$ Formula of oxide of iodine would be $I _{2} O _{5}$.
$\frac{80}{16}=5$ and $\frac{254}{2}=127$