Question

Dimethyl glyoxime and ${NaHSO}_3/{NH}_{4}CNS$ are used to distinguish and separate ${Cu}^{2+}$ and ${Ni}^{2+}$. These are used in order :

• A. ${HSO}_3^{-}/{CNS}^{-}$ then $DMG$
• B. $DMG$ then ${HSO}_3^{-}/{CNS}^{-}$
• C. at random
• D. given reagents are not suitable

Answer 1

The correct option is A ${HSO}_3^{-}/{CNS}^{-}$ then $DMG$

Dimethyl glyoxime and ${NaHSO}_3/{NH}_{4}CNS$ are used to distinguish and separate ${Cu}^{2+}$ and ${Ni}^{2+}$. These are used in order ${HSO}_3^{-}/{CNS}^{-}$ then $DMG$. Ni(II) ions form red ppt with DMG whereas Cu(II) ions form ppt with ${NaHSO}_3/{NH}_{4}CNS$.