InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
A mixture consistsof A (yellow solid)and B (colourless solid) whichgivesfilaccolour inflame. a. Themixture gives blackprecipitate C onpassingH_(2)S gas b. C issolublein aquaandon evaportationof aquaregainand adding SnCI_(2) givesgreyish -black precipitateD c. The saltsolutionwith NH_(4)OH givesa brownprecipitate . i. The sodiumextractof the salt with C CI_(4)//FeCI_(3) AgNO_(2) solutionwhichisinsoluble in NH_(3) Identify A and Band the precipitate C and D |
|
Answer» Solution :`A: KI,B : HGI_(2) , C : HgS , D : Hg` Amixtureconsistsof a (yellow solid ) and B (colourless solid) which giveslilac colourin flame lilaccolour come frompiotassium ions . Mixturegives blackprecipitate Con passing `H_(2)S` gas C issolublein aquaregain it must be HgS .Oneveorationof aquaregainand adding `SnCI_(2)` it givea greyish-blackprecipitate D .This must be mercury .The saltsolutionwith `NH_(4)OH` gives a brownprecipitate.it mustbe iodide of Millon's basemercuriciodide .The sodiumextractof the salt with `C CI_(4)//FeCI_(3)` gives a violet LAYER .Thisconformiodide .Thesodium extractgives a yellowprecipitatewith `AgNO_(3)` solution which is insoloble in `NH_(3)` This alsoconform iodide `HgI_(2) + H_(2)S rarr underset(Black)(HgS darr )+ 2HI` `HgS overset("Aqua regia")rarr HgCI_(2)` (SOLUBLE) `HgCI_(2) overset(SnCI)rarr SnCI_(4) +underset(Black)(Hg)` ltbr? `2KI +HgI_(2) rarr underset("Nessler's reagent")(K_(2)HgI_(4))` `K_(2)HgI_(4) overset(NH_(3))rarr underset("Iodide of million's base")(H_(2)N-Hg-O-Hg-I)` With sodium extract: `2NaI +2FE^(3+) overset( C CI_(4))rarr I_(2) +2Na^(o+) +Fe^(2+)` `AgNO_(3) +NaI rarr AGi darr + NaNO_(3)` `AgI` is the yellow precipitate insoluble in ammonium hydroxide. |
|