Question

Balanced by the chemical equation by lion electron method.

Zn+NO3- GIVES ZN2+ + NO2

Answer 1

${\sf Zn+NO_3^-→Zn^{+2}+NO}$

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⠀⠀Ion-Electron Method

1. Write both the half reaction :

${\sf Zn→Zn^{+2} }$ (Reduction Reaction )

${\sf NO_3^-→NO }$ (Oxidation Reaction)

2. Atoms other than H and O are balanced :

Reaction is already balanced , so no change in reaction.

3. Balance O-atoms by the addiction of $\underline{\bf H_2O}$ to another side :

${\sf Zn→Zn^{+2}}$

${\sf NO_3^-+4H^+→NO+2H_2O }$

4. Balance H-atoms by the addiction of $\underline{\bf H^{+}}$ to another side :

${\sf Zn→Zn^{2+}}$

${\sf NO_3^- + 4H^+ →NO+2H_2O}$

5. Now balance the charge by addiction of electron :

${\sf Zn+2e^- →Zn^{+2} }$

${\sf NO_3^{-}+4H^+→NO+2H_2O+3e^- }$

6. Multiply Half reduction reaction by 3 and Half Oxidation Reaction by 2 and then add the two half reaction :

${\sf Zn+2e^-→Zn^{+2}\:\:\:\:\:×3}$

${\sf NO_3^- + 4H^+→NO+2H_2O+3e^-\:\:\:\:\:\:\:×2}$

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${\sf 3Zn+6e^-+2NO_3^-+8H^+→3Zn^{+2}+2NO+4H_2O+6e^- }$

Final reaction is ,

${\sf \red{3Zn+2NO_3^-+8H^+→3Zn^{+2}+2NO+4H_2O}}$