H2(g) + Zn(NO3)2(aq) → NO(g) + Zn2+(aq)
acidic environment
Zn(NO3)2(aq) + 8 H+(aq) + 6 e– → 2 NO(g) + Zn2+(aq) + 4 H2O(l)
[H2(g) → 2 H+(aq) + 2 e–] × 3
sum and eliminate common species
3 H2(g) + Zn(NO3)2(aq) + 2 H+(aq) → 2 NO(g) + Zn2+(aq) + 4 H2O(l)