A white substance (A) reacts with dilute H_(2)SO_(4) to produce a colourless gas (B) and a colourless solution ( C).The reaction between (B) and acidified K_(2)Cr_(2)O_(7) solution produces a green solution and a slightly coloured precipitate (D).The substance (D)burns in air to produce a gas (E) which reacts with (B) to yield (D) and a colourless liquid. Anhydrous copper sulphate is turned blue on addition of this colouless liquid.Addition of aqueous NH_(3) or NaOH to ( C) produces first a white precipitate which dissolves in the excess of the respective reagent to produce a clear solution in each case. Identify (A),(B),( C),(D) and (E).

A white substance (A) reacts with dilute H_(2)SO_(4) to produce a colo

1.	A white substance (A) reacts with dilute H_(2)SO_(4) to produce a colourless gas (B) and a colourless solution ( C).The reaction between (B) and acidified K_(2)Cr_(2)O_(7) solution produces a green solution and a slightly coloured precipitate (D).The substance (D)burns in air to produce a gas (E) which reacts with (B) to yield (D) and a colourless liquid. Anhydrous copper sulphate is turned blue on addition of this colouless liquid.Addition of aqueous NH_(3) or NaOH to ( C) produces first a white precipitate which dissolves in the excess of the respective reagent to produce a clear solution in each case. Identify (A),(B),( C),(D) and (E).
Answer» Solution :`ZnS+H_(2)SO_(4)to ZnSO_(4) + H_(2)S` `Cr_(2)O_(7)^(2-) + 3H_(2)S+8H^(+) to 2Cr^(3+) ("green solution")+3S DARR +7H_(2)O` `S+O_(2) to SO_(2) , 2H_(2)S +SO_(2) to 2H_(2)O+3S` `ZN^(2+)+2OH^(-) toZn(OH)_(2) darr` (white) `Zn^(2+)+2NH_(3)+ H_(2)O hArrZn(OH)_(2) darr("white")+NH_(4)^(+)` `Zn(OH)_(2) darr +4NH_(3) HARR [Zn(NH_(3))_(4)]^(2+) +2OH^(-)`