11. Conservation of Mass,       Charge, and Energy   Previous PageNext Page
       Conservation of Electrons

For electrons to balance properly, three moles of H must be oxidised for every mole of NO3- reduced:

3 (+1) + (-3) = 0

and the reaction can be written

In any reaction in aqueous solution, one is at liberty to assume as many H2O,
H+, or OH- as are required to balance the reaction, using H2O and H+ under acidic conditions, or and OH- if the solution is basic. The redox (oxidation - reduction) part of the balancing has been done, and what remains is only an accounting for O and H atoms. One possible answer is

This has accounted for the three hydrogen atoms and the negative charge. The equation is correct for basic solutions where OH- ions are present.

The planar, delocallised nitrate ion

Formula NO3-
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