Question

In a particular redox reaction, no2– is oxidized to no3– and ag is reduced to ag. complete and balance the equation for this reaction in acidic solution. phases are optional.

Answer 1

Reduction Reaction:

Ag⁺ + 1e⁻ → Ag ------ (1)

Oxidation Reaction:

NO₂⁻ → NO₃⁻ + 2e⁻

Balance Oxygen atoms, by adding H₂O to side having less number of O atoms, and H⁺ to side having greater number of O atoms.

NO₂⁻ + H₂O → NO₃⁻ + H⁺ + 2e⁻

Balance the H⁺'s,

NO₂⁻ + H₂O → NO₃⁻ + 2 H⁺ + 2e⁻ ------ (2)

Multiply eq. 1 by 2 to balance the number of electrons in overall reaction.

2 Ag⁺ + 2e⁻ → 2 Ag ----- (3)

Compare eq. 2 and 3,

NO₂⁻ + H₂O → NO₃⁻ + 2 H⁺ + 2e⁻
2 Ag⁺ + 2e⁻ → 2 Ag
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NO₂⁻ + H₂O + 2 Ag⁺ → NO₃⁻ + 2 Ag + 2 H⁺