Question

An element of group ` 14` form a red coloured mized oxide (A) which on treatment with conc `GnO_3` gives compound (B) , (B) reacts with `HCl` to produce a choloride (C) , which is insolubil in cold water hut solububle in ot water . (A) on reaction with conc `HCl` produces (C) . Identify (A), (B) and (C) .

Answer 1

Lead (Pb) forms a red-coloured mixed osice , known as red lead `Pb_3 O_4` (A) , which is a mixed oxide of `PbO_2` and `PbO` in the ration `1: 2`.
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`underset ((A)) (Pb_3O_4) + 4 HN underset (conc)(NO_3 )rarr (2PbNO_3)_2 +PbO_2 +2H_2 O`
`underset ((B)) (Pb (NO_3)_2) + 2HCl rarr underset (White ppt . ) ((C )) (PnCl_2harr) + 2 HNO_3`
` (C ) PbCl_2` is insoluyble in cold wate but soluble in hot water .
` underset ((A)) (Pb _3 O_4 )+underset (conc)(8 HCk) rarr underset ((C))(3 P bCl_2) + 4H_2O +Cl_)2`
`Pb _3O_4` actgs as an oxidising agent and oxidses `2 Cl^(Θ) rarr Cl_2` Hence . (A) is `Pb_3O_4` , red lada ltbgt (B) is `Pb(NO_3)` lead nitrate
(C) is ` PbCl_2` lead (II) chloride .