Purification an...

In a solution containing 2 Cu²⁺ and Cd²⁺, dil. H₂SO₄ is added followed by iron filings. The solution is warmed and NH₄OH is added to reduce the acidity followed by passing of H₂S gas. The ppt. obtained will be

An aqueous solution of a substance gives a white precipitate on treatment with dilute hydrochloric acid, which dissolves on heating. When hydrogen sulphide is passed through the hot acidic solution, a black precipitate is obtained. The substance is a

When borax is heated in a Platinum loop, the transparent bead formed contains:

A glassy bead formed by heating borax on a platinum wire loop is

Which of the following element forms dark green coloured salts?

In the second group of qualitative analysis, H₂S is passed through a solution acidified with dil. HCl in order to

In the following sequence of reaction, identify the compound (C).

Ammonium salt gives brown colour with alkaline solution of Nessler’s reagent to form iodide of Millon’s base. The formula of this compound is

A coloured ppt. is obtained when H₂S gas is passed through an aqueous solution of salt in presence of ammonium hydroxide. The ppt. dissolves in dil. HCl and reacts with NaOH to give white ppt. which on standing turns into brown/black mass. The brown/black mass on fusion with KNO₃ and Na₂CO₃ gives green mass. The cation of the salt is

The compound (X) on heating gives a colourless gas. The residue is dissolved in water to obtain (Y). Excess CO2 is bubbled through aqueous solution of (Y), (Z) is formed. (Z) on gentle heating gives back (X). The compound (X) is: