A light bluish-green crystalline compound respond to the following tests : (I) Its aq. solution gives a brown precipitate with alkaline K 2 [ HgI 4 ] solution. (II) Its aq. solution gives a blue c

Question

A light bluish-green crystalline compound respond to the following tests :

(I) Its aq. solution gives a brown precipitate with alkaline $K_{2} [HgI_{4}]$ solution.

(II) Its aq. solution gives a blue colour ppt. with $K_{3} [Fe (CN)_{6}]$ solution.

(III) Its solution in hydrochloric acid gives a white precipitate with $BaCl_{2}$ solution.

Ions present in bluish green crystalline compound must be :-

TestHub · Accepted Answer

Explain Question:

Identifying cations and anions in a salt using standard qualitative analysis tests.

Concept:

Salt Analysis (Qualitative Inorganic Analysis)

Solution:

Test (i): A brown precipitate with alkaline K₂[HgI₄] (Nessler’s Reagent) confirms the ammonium ion (NH₄⁺).

Test (ii): A blue precipitate (Turnbull's Blue) with potassium ferricyanide (K₃[Fe(CN)₆]) confirms the ferrous ion (Fe²⁺).

Test (iii): A white precipitate with BaCl₂ that is insoluble in HCl confirms the sulfate ion (SO₄²⁻).

Calculation:

Ions Identified: Fe²⁺, NH₄⁺, and SO₄²⁻.

Compound: Likely Mohr’s Salt (FeSO₄ ⋅ (NH₄)₂SO₄ ⋅ 6H₂O).

Chemistry - Salt Analysis Question with Solution | TestHub