Question

$A, B$ and $C$ are three elements forming a part of compound in oxidation states of $+2, +5$ and $-2$ respectively. What could be the compound if molecule is neutral?

• A. $A_{2}(BC)_{2}$
• B. $A_{2}(BC_{4})_{3}$
• C. $A_{3}(BC_{4})_{2}$
• D. $ABC$

Answer 1

Answer: (C)

$A_{3}(BC_{4})_{2}$
$3 (+ 2) + 2[ 1 (+ 5) + 4 (- 2)] = 6 + 2 (- 3) = 0$
As the molecule is neutral, the sum of oxidation numbers must be zero