A silver compound (A) which leaves black stain on skin gives white precipitate with hypo solution. White ppt. changes to black due to formation of B. This black ppt. dissolves in aqueous NaCN to give C which on treatment with zinc gives a metal D. A, B, C and D respectively are

Zinc(II) ion on reaction with NaOH first give a white precipitate which dissolves in excess of NaOH due to the formation of :

Which of the following complex will give white ppt. with BaCl_(2) solution ?

An aqueous solution of compound 'A' gives white precipitate with 2M HCl .The precipitate becomes black on addition of aqueous NH_(3) due to formation of 'B' . 'B' dissolves in aquaregia. 'A' and 'B' are:

Which of the following will not give white precipitate with ammoniacal silver nitrate solution ?

Which one of the following does not give white precipitate with acidified silver nitrate solution?

The salt which in solution gives a pale green ppt. with NaOH soln. & a white ppt. with barium chloride soln is:

When a KI solution is added to a metal nitrate, a black precipitate is produced which dissolves in an excess of KI to give an organge solution. The metal ion is:

A white substance (A) reacts with dilute H_(2)SO_(4) to produce a colourless suffocating gas (B) and a colourless solution (C )/ The reaction of gas (B) with potassium iodate and starch solution produce a blue colour solution. Aqueous Solution of (A) gives a white precipitate with BaCl_(2) solution which is soluble in dilute HCl . Addition of aqueous NH_(3) or NaOH to (C ) produced first a precipitate which dissolves in excess of the respective reagent to poduced a clear solution. Similarly addition of excess of potassium ferrocyanide to (C ) produced a precipitate (D) which also dissolves in aqeous NaOH giving a clear solution. Identify (A),(B),(C ) and (D ). Write the equation of the reactions involved.

The aqueous solution of salt gives white ppt with lead acetate solution which is insoluble in hot water and nitric acid .The salt contains

An element A reacts with water to form a compound B which is used in white washing. The compound B on heating forms an oxide C which on treatment with water gives back B. Identify A, B and C and give the reactions involved.