Chemistry

Problem

Which of the following compounds after mixing can produce blue colouration? (I)

\text{K}_4[\text{Fe}(\text{CN})_6]

and

\text{FeCl}_3

solution (II)

\text{NH}_4\text{OH}

and

\text{CuSO}_4

solution (III) Adding anhydrous

\text{CuSO}_4

to water (IV)

\text{NH}_4\text{OH} + \text{NiSO}_4

solution Choose the correct code: a. I, II, III b. II, III c. I, III d. I, II, III, IV