Question

Sodium extract is heated with concentrated $HNO_{3}$ before testing for halogens because :

• A. $Ag_{2}S$ and AgCN are soluble in acidic medium.
• B. Silver halides are totally insoluble in nitric acid.
• C. $S^{2 -}$ and $CN^{-}$ , if present, are decomposed by conc. $HNO_{3}$ and hence do not interfere in the test.
• D. Ag reacts faster with halides in acidic medium

Answer 1

Answer: (C)

$S^{2 -}$ and $CN^{-}$ ions if present are decomposed by conc. $HNO_{3}$ and hence do not interfere in the test.