Which of the following statement(s) is/are true?

Options

A. Titan yellow solution gives red colouration with a neutral solution contaning `Mg^(2+)` ions.
B. Solution of nitrite is decomposed by sulphamic acid.
C. `Fe^(2+)` ions give brown colour precipitate with `[Fe(CN)_(6)]^(3-)` ions solution.
D. Green precipitate of `Cr(OH)_(3)` is soluble in `Na_(2)O_(2)`.

Answer

B, D

Explanation

(a) Red colouration is obtained in alkaline solution.
(b) `HO.SO_(2).NH_(2)+HNO_(2) rarr N_(2)uarr +2H^(+)+SO_(4)^(2-)+H_(2)O`
(c) `Fe^(2+) +Fe(CN)_(6)^(3-) rarr Fe_(3)[Fe(CN)_(6)]_(2)` (Turnbull's blue)
(d) `Cr(OH)_(3) overset(Na_(2)O_(2))rarr CrO_(4)^(2-)`