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How is ammonia only oxidised in this?

a In the first stage, ammonia is converted into nitrogen monoxide and the following equilibrium is established.
4NH3(g)  5O2(g) ⇌ 4NO(g)  6H2O(g) ∆H  –905 kJ mol–1
In terms of redox, state what happens to the ammonia in the forward reaction.

The nitrogen in NH3 goes from an oxidiation state of -3 to +2
The hydrogen in NH3 goes from an oxidation state of +3 to +1.
So how am I meant to tell whether ammonia is oxidised or reduced ??

Reply 1

Ani240

Since the oxidation number of Nitrogen went from negative to positive it is oxidised while the hydrogen is reduced

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Reply 2

Helpstudent402

Original post by Ani240

Since the oxidation number of Nitrogen went from negative to positive it is oxidised while the hydrogen is reduced

But why as a whole is ammonia considered to be oxidised when both components of the compound have different things happening to them???

Reply 3

Ani240

https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.quora.com/How-can-ammonia-be-a-weak-reducing-agent-and-a-strong-base%23:~:text%3DHow%2520is%2520ammonia%2520a%2520reducing%2520agent%253F%26text%3DAs%2520you%2520can%2520see%252C%2520here,it%2520is%2520a%2520reducing%2520agent.&ved=2ahUKEwimnY7isszwAhXBQ3wKHZakDKwQFjABegQIBBAF&usg=AOvV

Since NH3 is a reducing agent,it gets oxidised

Reply 4

Pigster

Original post by Helpstudent402

But why as a whole is ammonia considered to be oxidised when both components of the compound have different things happening to them???

"ammonia" doesn't get oxidised. The nitrogen atom in ammonia gets oxidised.

Reply 5

jack_harrison

Might want to double check your assignment of ammonia's hydrogen oxidation state. The hydrogens in both ammonia and water are in the +1 oxidation state, so nothing happens to them during this reaction.

(edited 2 years ago)

Reply 6

deskochan

The nitrogen in NH3 goes from an oxidation state of -3 to +2 (Right)
The hydrogen in NH3 is without any change in the oxidation state.
4NH3(g) + 5O2(g) ⇌ 4NO(g) + 6H2O(g)
NH3 is a reducing agent and oxygen gas is an oxidizing agent and the oxygen is reduced by NH3 from 0 to -2.