6. Microorganisms called denitrifying bacteria that grow in waterlogged soil convert NOs ions into N2O gas as they feed on dead plant tissue (empirical formula CH:O), converting it to carbon dioxide CO and water H:O. Balance the redox reaction in slightly acidic medium that describes this conversion:
Solution
NO3^- (aq) + CH2O(s) ----------> N2O(g) + CO2(g) + H2O(l)
oxidation half reaction Reduction half reaction
CH2O(s) ------------> CO2(g) NO3^- (aq) ------------> N2O(g)
CH2O(s) +H2O------------> CO2(g) 2NO3^- (aq) ------------> N2O(g)+5H2O
CH2O(s) +H2O------------> CO2(g) 2NO3^- (aq) ------------> N2O(g)+5H2O
CH2O(s) +H2O------------> CO2(g)+4H^+(aq) 2NO3^- (aq)+10H^+ (aq) --------> N2O(g)+5H2O
CH2O(s) +H2O------------> CO2(g)+4H^+(aq)+4e^- 2NO3^- (aq)+10H^+ (aq) +8e^- --------> N2O(g)+5H2O
2CH2O(s) +2H2O------------> 2CO2(g)+8H^+(aq)+8e^-
2NO3^- (aq)+10H^+ (aq) +8e^- --------> N2O(g)+5H2O
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2CH2O9s) + 2NO3^-(aq) + 2H^+ (aq) -----------> 2Co2(g) + N2O(g) + 3H2o(l)
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