WO3+3H2=W+3H2O
W{6+} + 6e = W{0} /1
H2{0} - 2e = 2H{+} /3
10NH3+6KMnO4+9H2SO4=5N2+
+6MnSO4+3K2SO4+24H2O
2N{3-} - 6e = N2{0} /5
Mn{7+} + 5e = Mn{2+} /6
