Ammonia Redox Reactions
React ammonia with copper oxide and chlorine
What this lesson covers
Why it matters
Ammonia is usually a base, but here it acts as a reducing agent — stripping oxygen from copper oxide, or reducing chlorine to HCl. Watch how nitrogen gas emerges from both reactions.
The idea in plain words
Analyze the redox change: Copper goes from +2 to 0. Nitrogen goes from -3 to 0. Who is the reducing agent?
Predict first
When ammonia reacts with heated copper oxide, what happens to the ammonia?
Ammonia acts as a reducing agent. It removes oxygen from CuO, becoming oxidized itself to N₂.
- It gains oxygen to form nitric acid
- It loses hydrogen and is oxidized to nitrogen gas — correct
- It acts as a base and forms ammonium oxide
What you do
Run both reactions. Observe the formation of reddish-brown copper in the first and the reduction of chlorine to HCl in the second. Note the common product.
Check yourself
In the reaction 3CuO + 2NH₃ → 3Cu + 3H₂O + N₂, what is the visible change in the solid?
CuO (black) is reduced to Cu (reddish-brown).
What is the common gaseous product in both ammonia reactions?
Both equations produce N₂.
In 2NH₃ + 3Cl₂ → N₂ + 6HCl, ammonia acts as a:
Ammonia is oxidized to N₂, so it reduces Cl₂ to HCl.
- Black powder turns to reddish-brown metal — correct
- Black powder turns to white ash
- The solid dissolves into a blue solution
- Hydrogen gas
- Nitrogen gas — correct
- Ammonia gas
- Chlorine gas
- Reducing agent — correct
- Oxidizing agent
- Catalyst