Write the reaction equation: H2O → H2 → NH3 → (NH4) 2SO4 → NH4NO2 → N2

1) 2H2O → 2H2 ↑ + O2 (decomposition reaction);
2) 3H2 + N2 → 2NH3 ↑ (compound reaction);
3) 2NH3 + H2SO4 → (NH4) 2SO4 (compound reaction);
4) (NH4) 2SO4 + Ba (NO2) 2 → 2NH4NO2 + BaSO4 ↓ (exchange reaction);

2NH₄⁺ + SO₄^2- + Ba²⁺ + 2NO₂^– → 2NH₄⁺ + 2NO₂^– + BaSO₄↓;

SO₄^2- + Ba²⁺ → BaSO₄↓;

5) NH4NO2 → N2 + 2H2O (decomposition reaction).