Amongst the various ores of a metal (M) (sulphide, carbonates, oxides, hydrated or hydroxides) two ores [X] and [Y] show the following reactivity.
(i) [X] on calcination gives a black solid (S), water and a colourless gas which produces milkyness when passed through lime water. But this colourless gas does not decolourise the acidified KMNO 4 .
(ii) [X] dissolved in dilute HCl on reaction with KI gives a white precipitate (P) and iodine gas.
(iii) [Y] on roasting at high temperature gives metal (M) and a gas (G 1 ) which turns starch iodate solution blue.
(iv) [Y] on reaction with dilute HCl gives a white precipitate (MS) and another gas (G 2 ) which turns lead acetate solution black and also reacts with gas (G 1 ) to precipitate colloidal sulphur in presence of moisture.
The M, S, [X] and [Y] gives greenish blue flame.
(i) The metal ores [X] and [Y] are respectively :
Text Solution
Verified by Experts(i) [X]
(i) [X] = CuCO 3. Cu(OH) 2 or 2CuCO 3 .Cu(OH) 2 ; [Y] = Cu 2 S or CuFeS 2
CuCO 3 .Cu(OH) 2 
CuO (S) + CO 2 + H 2 O ;
[Y] = Cu 2 S or CuFeS 2
2Cu 2 S + 3O 2 ⎯→ 2Cu 2 O + 2SO 2 ; Cu 2 S + 2Cu 2 O ⎯→ 6Cu (M) + SO 2 (g)
5SO 2 + 2 Ι O 3 – + 4H 2 O ⎯→ Ι 2 + SO 4 2– + 8H +
Ι 2 + strach ⎯→ blue colour
(ii) It is sulphide ore (Cu 2 S or CuFeS 2 ) & is called as copper glance or copper pyrite; S 2– gives yellow ppt. of CdS with CdCO 3 suspension.
(iii) G 1 = SO 2 ; It can increase its oxidation state from +4 to +6 & decrease from +4 to 0 or –2.
(iv) CuCO 3 + 2HCI ⎯→ CuCl 2 + CO 2 + H 2 O; CuCl 2 + 2KI ⎯→ CuI 2 + 2KCI; 2CuI 2 ⎯→ Cu 2 I 2 + Ι 2
(v) CuCO 3 .Cu(OH 2 ) 
CuO ↓ (black) + CO 2 + H 2 O
CuCO 3 . Cu(OH) 2 + 4HCl ⎯→ 2CuCl 2 + 3H 2 O + CO 2 ;
2CuCl 2 + 4KI ⎯→ Cu 2 Ι 2 ↓ (white) + Ι 2 + 4KCI
Prepare Smarter with CGP Edu
Get practice questions, solutions, and test series in one place.
Write a Review
Share your experience with this question and solution.
Commentary
Send your comment, doubt, correction, or feedback to admin.
Similar Questions
Explore conceptually related problems