# 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?

Apr 24, 2017

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

$K \left(s\right) + {H}_{2} O \left(l\right) \rightarrow K O H \left(a q\right) + \frac{1}{2} {H}_{2} \left(g\right) \uparrow$

#### Explanation:

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

$2 K \left(s\right) + 2 {H}_{2} O \left(l\right) \rightarrow 2 K O H \left(a q\right) + {H}_{2} \left(g\right) \uparrow$

And for the oxidation of ammonia $\left(b\right)$:

$N {H}_{3} \left(g\right) + {O}_{2} \left(g\right) \rightarrow N {O}_{2} \left(g\right) + \frac{3}{2} {H}_{2} \left(g\right)$, and double again to gives................:

$2 N {H}_{3} \left(g\right) + 2 {O}_{2} \left(g\right) \rightarrow 2 N {O}_{2} \left(g\right) + 3 {H}_{2} \left(g\right)$.

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?