JEE Main 2018 (Offline) | Practical Organic Chemistry Question 95 | Chemistry

A solution containing a group-IV cation gives a precipitate on passing H₂S. A solution of this precipitate in dil.HCl produces a white precipitate with NaOH solution and bluish-white precipitate with basic potassium ferrocyanide. The cation is :

Co²⁺

Ni²⁺

Mn²⁺

Zn²⁺

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MCQ (Single Correct Answer)

-1

Sodium salt of an organic acid ‘X’ produces effervescence with conc. H₂SO₄. ‘X’ reacts with the acidified aqueous CaCl₂ solution to give a white precipitate which decolourises acidic solution of KMnO₄. ‘X’ is :

CH₃COONa

Na₂C₂O₄

C₆H₅COONa

HCOONa

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MCQ (Single Correct Answer)

-1

Sodium extract is heated with concentrated HNO₃ before testing for halogens because :

Silver halides are totally insoluble in nitric acid.

Ag₂S and AgCN are soluble in acidic medium.

S₂⁻ and CN⁻, if present, are decomposed by conc. HNO₃ and hence do not interfere in the test.

Ag reacts faster with halides in acidic medium.