The products of the thermal decomposition of ammonium trioxonitrate(v) are

Ammonium trioxonitrate(V) is the IUPAC name for ammonium nitrate, NH₄NO₃. When heated gently (thermal decomposition), it breaks down as follows:

\[\text{NH}_4\text{NO}_3 \xrightarrow{\text{heat}} \text{N}_2\text{O} + 2\text{H}_2\text{O}\]

The products are dinitrogen monoxide (N₂O, also known as nitrous oxide or laughing gas) and water (H₂O).

To verify, check that the equation is balanced:

• N: 2 on each side (1 from NH₄⁺ and 1 from NO₃^- on the left; 2 in N₂O on the right).
• H: 4 on each side (4 in NH₄⁺ on the left; 4 in 2H₂O on the right).
• O: 3 on each side (3 in NO₃^- on the left; 1 in N₂O + 2 in 2H₂O on the right).

The other options are incorrect: NO₂ and H₂O would not balance correctly with the given reactant; N₂O and O₂ would leave hydrogen unaccounted for; and NO₃ is not a stable molecular product of thermal decomposition.