1. Gentle Heating (below 200°C):
Cu(NO₃)₂ (s) → CuO (s) + 2 NO₂ (g) + ½ O₂ (g)
This reaction produces copper(II) oxide (CuO), nitrogen dioxide (NO₂), and oxygen gas (O₂).
2. Strong Heating (above 200°C):
2 Cu(NO₃)₂ (s) → 2 CuO (s) + 4 NO₂ (g) + O₂ (g)
This reaction also produces copper(II) oxide, nitrogen dioxide, and oxygen gas, but with a different stoichiometry.
Key points:
* Decomposition: Copper nitrate decomposes into simpler compounds when heated.
* Red-brown gas: Nitrogen dioxide (NO₂) is a reddish-brown gas.
* Oxygen gas: Oxygen gas is colorless and odorless.
* Copper(II) oxide: Copper(II) oxide is a black solid.
Note: The decomposition reaction is usually carried out in a fume hood because nitrogen dioxide is a toxic gas.
