2\. A : Electroplating | Complete and balance the electrode reactions ------------------------------|-------------------------------------- Electroplating of an article with nickle | 10\. Dissociation of aq. nickle sulphate | NiSO₄ ............... + ............... | H₂O ............... + ............... 11\. Reaction at cathode [article to be plated] | Ni²⁺ + ............... ............... [Ni deposited on article] 12\. Reaction at anode [block of active-nickle] | Ni - ............... ............... [product nil - Ni²⁺ ions] Electroplating of an article with silver | 13\. Dissociation of sodium silver cyanide | Na[Ag(CN)₂] ............... + ............... + ............... | H₂O ............... + ............... 14\. Reaction at cathode [article to be plated] | Ag¹⁺ + ............... ............... [Ag deposited on article] 15\. Reaction at anode [block of active-silver] | Ag - ............... ............... [product nil - Ag¹⁺ ions]

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2.A : Electroplating | Complete and balance the electrode reactions ------------------------------|-------------------------------------- Electroplating of an article with nickle | 10\. Dissociation of aq. nickle sulphate | NiSO₄ Ni²⁺ + SO₄^2- | H₂O H¹⁺ + OH^1- 11\. Reaction at cathode [article to be plated] | Ni²⁺ + 2e^- Ni [Ni deposited on article] 12\. Reaction at anode [block of active-nickle] | Ni - 2e^- Ni²⁺ [product nil - Ni²⁺ ions] Electroplating of an article with silver | 13\. Dissociation of sodium silver cyanide | Na[Ag(CN)₂] Na¹⁺ + Ag¹⁺ + 2CN^1- | H₂O H¹⁺ + OH^1- 14\. Reaction at cathode [article to be plated] | Ag¹⁺ + 1e^1- Ag [Ag deposited on article] 15\. Reaction at anode [block of active-silver] | Ag - 1e^1- Ag¹⁺ [product nil - Ag¹⁺ ions]

2. A : Electroplating	Complete and balance the electrode reactions
Electroplating of an article with nickle
10. Dissociation of aq. nickle sulphate	NiSO₄ ⇌ …………… + ……………
	H₂O ⇌ …………… + ……………
11. Reaction at cathode [article to be plated]	Ni²⁺ + …………… ⟶ …………… [Ni deposited on article]
12. Reaction at anode [block of active-nickle]	Ni - …………… ⟶ …………… [product nil - Ni²⁺ ions]
Electroplating of an article with silver
13. Dissociation of sodium silver cyanide	Na[Ag(CN)₂] ⇌ …………… + …………… + ……………
	H₂O ⇌ …………… + ……………
14. Reaction at cathode [article to be plated]	Ag¹⁺ + …………… ⟶ …………… [Ag deposited on article]
15. Reaction at anode [block of active-silver]	Ag - …………… ⟶ …………… [product nil - Ag¹⁺ ions]

2.A : Electroplating	Complete and balance the electrode reactions
Electroplating of an article with nickle
10. Dissociation of aq. nickle sulphate	NiSO₄ ⇌ *Ni²⁺* + *SO₄^2-*
	H₂O ⇌ *H¹⁺* + *OH^1-*
11. Reaction at cathode [article to be plated]	Ni²⁺ + *2e^-* ⟶ Ni [Ni deposited on article]
12. Reaction at anode [block of active-nickle]	Ni - *2e^-* ⟶ *Ni²⁺* [product nil - Ni²⁺ ions]
Electroplating of an article with silver
13. Dissociation of sodium silver cyanide	Na[Ag(CN)₂] ⇌ *Na¹⁺* + *Ag¹⁺* + *2CN^1-*
	H₂O ⇌ *H¹⁺* + *OH^1-*
14. Reaction at cathode [article to be plated]	Ag¹⁺ + *1e^1-* ⟶ Ag [Ag deposited on article]
15. Reaction at anode [block of active-silver]	Ag - *1e^1-* ⟶ *Ag¹⁺* [product nil - Ag¹⁺ ions]

1. Electrolysis	Complete and balance the electrode reactions
a. Electrolysis of fused lead bromide
1. Dissociation of lead bromide	PbBr₂ ⇌ …………… + …………… [ions present Pb²⁺, Br^1-] ]
2. Reaction at cathode [inert-graphite]	Pb²⁺ + …………… ⟶ …………… [product Lead metal]
3. Reaction at anode [inert-graphite]	Br^1- - …………… ⟶ …………… Br + Br ⟶ …………… [product Bromine vapours]
b. Electrolysis of acidified water
4. Dissociation of acidified water	H₂SO₄ ⇌ …………… + ……………
	H₂O ⇌ …………… + …………… [ions H¹⁺, SO₄^2-, OH^1-]
5. Reaction at cathode [inert-platinum]	H¹⁺ + …………… ⟶ ……………
	H + H ⟶ …………… [product Hydrogen gas]
6. Reaction at anode [inert-platinum]	OH^1- - …………… ⟶ ……………
	4OH ⟶ …………… + …………… [product oxygen gas]
c. Electrolysis of aq. copper sulphate [Active-copper electrode]
7. Dissociation of aq. copper sulphate	CuSO₄ ⇌ …………… + …………… [ions present — Cu²⁺, H¹⁺, SO₄^2-, OH^1-] H₂O ⇌ …………… + ……………
8. Reaction at cathode [copper (or Pt. or C)]	Cu²⁺ + …………… ⟶ …………… [product copper metal]
9. Reaction at anode [active copper]	Cu - …………… ⟶ …………… [product nil - Cu²⁺ ions]
[Inert-platinum electrode] Dissociation of aq. copper sulphate	CuSO₄ ⇌ …………… + …………… [ions present — Cu²⁺, H¹⁺, SO₄^2-, OH^1-] H₂O ⇌ …………… + ……………
Reaction at cathode [Pt. or Carbon or Cu]	Cu²⁺ + …………… ⟶ …………… [product copper metal]
Reaction at anode [inert-Pt. or C]	OH^1- - …………… ⟶ …………… 4OH ⟶ …………… + …………… [product oxygen gas]

2. B Electrorefining of copper	Complete and balance the electrode reactions
16. Dissociation of aq. copper sulphate	CuSO₄ ⇌ …………… + ……………
	H₂O ⇌ …………… + ……………
17. Reaction at cathode [pure thin sheet of Cu]	Cu²⁺ + …………… ⟶ …………… [Cu deposited on thin sheet]
18. Reaction at anode [impure block of active Cu]	Cu - …………… ⟶ …………… [product nil - Cu²⁺ ions]
Electrometallurgy of sodium
19. Dissociation of sodium chloride fused	NaCl ⇌ …………… + ……………
20. Reaction at cathode [inert - electrode]	Na¹⁺ + …………… ⟶ …………… [product Na metal]
21. Reaction at anode [inert - electrode]	Cl^1- - …………… ⟶ ……………
	Cl + Cl ⟶ …………… [product Cl₂ gas]
Electrometallurgy of aluminium
22. Dissociation of pure alumina	Al₂O₃ ⇌ …………… + ……………
23. Reaction at cathode [inert - electrode]	Al³⁺ + …………… ⟶ …………… [product Al metal]
24. Reaction at anode [inert - electrode]	O^2- - …………… ⟶ …………… ⟶ 3O₂ [product O₂ gas]

Chemistry

Electrolysis

Answer

Related Questions

During the electrolysis of molten lead bromide, which of the following takes place ?
Bromine is released at the cathode
Lead is deposited at the anode
Bromine ions gain electrons
Lead is deposited at the cathode

Here is an electrode reaction:
Cu ⟶ Cu²⁺ + 2e^-. [i.e. Cu – 2e^- ⟶ Cu²⁺]
At which electrode (anode or cathode) would such a reaction take place ? Is this an example of oxidation or reduction ?