To a solution of an unknown compound, a little dilute tetraoxosulphate (VI) acid was added with some freshly prepared iron (II) tetraoxosulphate (VI) solution. The brown ring observed after the addition of a stream of concentrated tetraoxosulphate (VI) acid confirmed the presence of?
A
CO\(^{2-}_{3}\)
B
Cl-
C
SO\(_{3}^{2-}\)
D
NO\(^{2-}_{3}\)
Verified Correct Answer: D.
Step-by-Step Mathematical Solution
NO\(_{3}^{-}\) is confirmed, then the brown ring is due to the formation of FESO\(_4\).NO
Source: WAEC / JAMB / NECO Classroom Archive (Record #4492)