(i) An aqueous solution of a compound A is acidic towards litmus and A is sublimed at about 300^(@) C. (ii) A on treatment withh an excess of NH_(4)SCN gives a red coloured B and on treatment with a solution of K_(4)[Fe(CN)_(6)] gives a red coloured compound B and on treatment withh a solution of K_(4)[Fe(CN)_(6)] gives a blue coloured compound C. (iii) A on heating with excess of K_(2)Cr_(2)O_(7) in presence of concentrated H_(2)SO_(4) evolves deep red vapours of D. (iv) On passing the vapours of D into a solution of NaOH and then adding the solutions of acetic acid and lead acetate, a yellow precipitate of compound E is obtained. Identify A to E and give chemical equations for the reactions at steps (ii) to (iv).

(i) An aqueous solution of a compound A is acidic towards litmus and A

1.	(i) An aqueous solution of a compound A is acidic towards litmus and A is sublimed at about 300^(@) C. (ii) A on treatment withh an excess of NH_(4)SCN gives a red coloured B and on treatment with a solution of K_(4)[Fe(CN)_(6)] gives a red coloured compound B and on treatment withh a solution of K_(4)[Fe(CN)_(6)] gives a blue coloured compound C. (iii) A on heating with excess of K_(2)Cr_(2)O_(7) in presence of concentrated H_(2)SO_(4) evolves deep red vapours of D. (iv) On passing the vapours of D into a solution of NaOH and then adding the solutions of acetic acid and lead acetate, a yellow precipitate of compound E is obtained. Identify A to E and give chemical equations for the reactions at steps (ii) to (iv).
Answer» Solution :(i) `PeCl_(3) overset("hydrolysis")underset("by" H_(2)O) to underset("ACETIC")underset("acidic")(Fe(OH)_(3) + 3HCl)` (ii) `4FeCl_(3) + 3NH_(4)SCN to Fe(SCN)_(3) + 3NH_(4)Cl` FERRIC THIOCYANATE (B) (red colour) `4FeCl_(3) + underset("Ferrioferro cyanide blue colour C")(3K_(4)[Fe(CN_(4))] to Fe_(4)[Fe(C CN)_(6)] + 12 kCL` (iii) `2FeCl_(3) + K_(2)Cr_(2)O_(7) + 3H_(2)SO_(4) to underset("Chromyl chloride (red) (D)")(Fe_(2)(SO_(4))_(3) + 2KCl + 2CrO_(2)Cl_(2) uarr + 3H_(2)O` (iv) `Cr_(2)O_(2)Cl_(2) + 2NaOH to Na_(2)CrO_(4) + 2HCl` `underset("Lead chromate")(Na_(2)CrO_(4)) + (CH_(3)COO)_(2)Pb to PbCrCO_(4)darr + 2CH_(3)COONa`