Question

Writing the half-reactions of a complex redox reaction i... Write balanced half-reactions for the following redox reaction: 2+ 4 Zn (aq)+ AsH 3(9)+8 OH (aq) -- 4 Zn(s)+H3A$O4(aq)+4 H2O() reduction: oxidation: X

Answer 1

1. Sol :-

Given reaction is :

4 Zn²⁺ (aq) + AsH₃ (g) + 8 OH^- (aq) ------------------> 4 Zn (s) + H₃AsO₄ (aq) + 4 H₂O (l)

Reduction half cell reaction is :

4 Zn²⁺ (aq) + 8e^- ------------------> 4 Zn (s)

Oxidation half cell reaction is :

AsH₃ (g) + 8 OH^- (aq) ------------------> H₃AsO₄ (aq) + 4 H₂O (l) + 8e^-

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2. Sol :-

Solution A	Solution B	Does precipitates form when A and B are mixed ?	Empirical formula of the precipitate
Sodium carbonate	Silver nitrate	Yes	Ag2CO3
Ammonium sulfide	Iron (II) chloride	Yes	Fe2S3
Cadmium acetate	Manganese (II) bromide	No

# Na₂CO₃ (aq) + 2 AgNO₃ (aq) ------------------> Ag₂CO₃ (s) ppt. + 2 NaNO₃ (aq)

# 3 (NH₄)₂S (aq) + 2 FeCl₃ (aq) ------------------> Fe₂S₃ (s) ppt. + 6 NH₄Cl(aq)

# Cd(CH₃COO)₂ (aq) + MnBr₂ (aq) ------------------> CdBr₂ (aq) + Mn(CH₃COO)₂ (aq)