Guest

1. To the mixture of aqueous solution of a Nitrate salt and Ferrous sulphate, con.H 2 SO 4 is slowly added through the slanted walls of the test tube. A brown ring is formed little above (nearly middle) the bottom of the test tube. a) What is the significance of this test? b) Which acts as reductant? c) What is the change of oxidation state of oxidant? d) What is the chemical composition of the Brown’s ring? e) Why con.H 2 SO 4 is added only through the slanted walls of the test tube? f) Write the related chemical equations for above chemical changes.

1.     To the mixture of aqueous solution of a Nitrate salt and Ferrous sulphate, con.H2SO4 is slowly added through the slanted walls of the test tube. A brown ring is formed little above (nearly middle) the bottom of the test tube.              


        a) What is the significance of this test?


        b) Which acts as reductant?


        c) What is the change of oxidation state of oxidant?


        d) What is the chemical composition of the Brown’s ring?


        e) Why con.H2SO4 is added only through the slanted walls of the test tube?


        f) Write the related chemical equations for above chemical changes.

Grade:Upto college level

1 Answers

Debjit Dutta
34 Points
12 years ago

a> The test is used to identify nitrate radical (NO3-)

b> Fe2+ is the reductant which gets oxidised to Fe3+

c>Fe is not in its usual +2 oxidation state but is in a +1 Oxidation state and the NO is also in a +1 oxidation state.

d>FeSO4.NO

e>the slowl adding concentrated sulphuric acid is such that the sulfuric acid forms a layer above the aqueous solution.

f>

 

NO3- + 3Fe2+ + 4H+ → 3Fe3+ + NO + 2H2O
[Fe(H2O)6]2+ + NO → [Fe(H2O)5(NO)]2+

Think You Can Provide A Better Answer ?

ASK QUESTION

Get your questions answered by the expert for free