Question

A metal salt solution gives a yellow precipitate with silver nitrate.The precipitate dissolves in dilute nitric acid as well as in dilute ammonia solution.The solution contains :
A. bromide ions
B. iodide ions
C. phosphate ions
D. chromate ions

Answer 1

Correct Answer - C
`Ag_(3)PO_(4)` is yellow precipitate which is soluble both in dilute ammonia solution and dilute `HNO_(3)`
`HPO_(4)^(2-) + 3Ag^(+) to Ag_(3)PO_(4) darr +H^(+)`
`Ag_(3)PO_(4)+2H^(+)toH_(2)PO_(4)^(-) darr+3Ag^(+),Ag_(3)PO_(4)darr +6NH_(3) to 3[Ag(NH_(3))_(2)]^(+)+PO_(4)^(3-)`
Pale yellow precipitate of `AgBr` is not soluble in dilute `HNO_(3)`,bright yellow precipitate of `Agl` is not soluble in both ,`Ag_(2)CrO_(4)` is obtained as red precipitate.