Question

Question #e3210

Answer 1

By separating the individual redox reactions, and assigning oxidation numbers.

Explanation:

Silver metal is oxidized to silver ion:

`stackrel(0)Ag rarr stackrel(+I)Ag^(+) +e^-` `(i)`

Nitrate ion is reduced to nitrogen monoxide:

`stackrel(+V)NO_3^(-) +4H^(+) + 3e^(-) rarr stackrel(+II)NO +2H_2O` `(ii)`

We add these half equations together to eliminate the electrons:

`3xx(i) + (ii):`

`3Ag + NO_3^(-) +4H^(+) rarr 3Ag^(+) + NO +2H_2O`

Is this balanced with respect to mass and charge? If it is not, it cannot be accepted as a representation of chemical (i.e. physical) reality.

While it might seem a little abstract to include electrons as fundamental reactants and products in these redox transfer processes, their use, as a convenient little fiction, allows us to address these types of problems.

For another example of this type of redox process, see here. And also see here and links for other examples.