IAS Chemistry Sample Questions ( Gas and Solutions ) (Read 6 times)

1. An aq soln of a gas X gives the fol reactions:

   1. It decolorizes an acidified soln of K2Cr2O7
   2. On boiling it with H2O2, cooling it and then adding an aq soln of BaCl2 a ppt insoluble in dil HCl is obtained.
   3. On passing H2S a white turbidity is obtained.

Identify X and give all reactions taking place.

2.  The gas liberated on heating a mix of 2 salts with NaOH gives a reddish brown ppt with an alk soln K2HgI4. The soln (aq) of the mix on treatment with BaCl2 gives a white pt which is sparingly solution in conc HCl. On heating the mix with K2Cr2O7 and conc H2SO4 red vap of A are produced. The aq soln of the mix gives a deep blue coloration B with pot ferricyanide soln. Identify the radicals and write balanced eqns for formation of A and B?