Question

Using whole number coefficients, how do we (a.) represent the oxidation of potassium metal by water; and (b.) represent the oxidation ammonia to give `NO_2`?

Answer 1

Well, I would balance `a.` to give........

`K(s) + H_2O(l) rarr KOH(aq) + 1/2H_2(g)uarr`

Explanation:

But you wanted whole number coefficients, so we double the creature to give..........

`2K(s) + 2H_2O(l) rarr 2KOH(aq) + H_2(g)uarr`

And for the oxidation of ammonia `(b)`:

`NH_3(g) + O_2(g) rarr NO_2(g) + 3/2H_2(g)`, and double again to gives................:

`2NH_3(g) + 2O_2(g) rarr 2NO_2(g) + 3H_2(g)`.

Both equation are balanced with respect to mass and charge. Sometimes I find the half-integral coefficients useful in that it is easier to assess stoichiometry this way.

Are these redox reactions? Why or why not?