Let's break down the problem step-by-step:
(i) Explain how this chemical equation shows ammonia acting as a reducing agent.
The given chemical reaction is:
[tex]\[ 4 \text{NH}_3(\text{g}) + 5 \text{O}_2(\text{g}) \rightarrow 4 \text{NO}(\text{g}) + 6 \text{H}_2\text{O}(\text{g}) \][/tex]
In this reaction, ammonia ([tex]\(\text{NH}_3\)[/tex]) is transforming into nitric oxide ([tex]\(\text{NO}\)[/tex]).
- As [tex]\(\text{NH}_3\)[/tex] is converted to [tex]\(\text{NO}\)[/tex], it loses hydrogen atoms and gains oxygen atoms.
- Losing hydrogen atoms and gaining oxygen atoms indicates that ammonia is being oxidized.
- Oxidation is the process where a substance loses electrons.
- In a redox (reduction-oxidation) reaction, the substance that is oxidized acts as a reducing agent, as it donates electrons to another substance.
Therefore, ammonia ([tex]\(\text{NH}_3\)[/tex]) acts as a reducing agent in this reaction because it donates electrons (gets oxidized) in the process.
(ii) Suggest a suitable catalyst for the reaction from the list of metals. Give a reason for your answer:
List of metals: aluminium, calcium, platinum, potassium, sodium
Suitable catalyst: Platinum
Reason: Platinum is highly efficient and stable in various chemical environments. It is commonly used as a catalyst in chemical reactions due to its ability to increase the reaction rate without being consumed in the process. Its high efficiency and stability make it a suitable choice for facilitating the reaction between ammonia and oxygen to produce nitric oxide and water.
