oxides of nitrogen? (1 Viewer)

[frezzel]

Hi i was wondering how many oxides of nitrogen there are that are involved in acid rain. Some sites have told me that there are 3 main ones: N₂O, NO , NO_{2. However, other sites have told me there are 2 main ones:} nitric oxide (NO) and nitrogen dioxide (NO₂). I have to construct a table for my assessment and i need to know which ones i am expected to research.


any help would be great.


Cheers, frezzel

 

[Jono_2007]

Hi i was wondering how many oxides of nitrogen there are that are involved in acid rain. Some sites have told me that there are 3 main ones: N₂O, NO , NO_{2. However, other sites have told me there are 2 main ones:} nitric oxide (NO) and nitrogen dioxide (NO₂). I have to construct a table for my assessment and i need to know which ones i am expected to research.
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The answer to this is there are THREE main constitutes of nitrogen oxides, in acin rain. NO, NO₂ and N₂O.
But The last two are sometime analysed together as NO_x

 

[frezzel]

thanks heaps, that helps alot...now i can get back to my assessment...yay...

 

[Ioup]

Isn't it NO2 thats the main cause of acid rain out of the Nitrogen Oxides?
NO2 is the only one thats soluble in water and reacts to form both nitric acid and nitrous acid. However, you could say that NO also contributes to the formation of acid rain as a large amount of it reacts with oxygen to form the NO2.

 

[Jono_2007]

Isn't it NO2 thats the main cause of acid rain out of the Nitrogen Oxides?

Tecnically it is the MAIN cause of acid rain , however it doesn't mean that NO isn't also a contributer.

NO2 is the only one thats soluble in water and reacts to form both nitric acid and nitrous acid. However, you could say that NO also contributes to the formation of acid rain as a large amount of it reacts with oxygen to form the NO₂.

Yes Nitrogen monoxide is always oxidising to nitrogen dioxide:

2NO (g) + O₂(g) -->2NO₂

 

[Dreamerish*~]

Technically, NO₂ is the only contributor to acid rain. NO could be said to be another contributor, but it contributes only by converting into NO₂ via the following reaction:

2NO + O₂ → 2NO₂

Ultimately, it is the NO₂ which reacts with water to form nitrous and nitric acids, which in turn make rain acidic. Therefore both sources were correct. The process of creating acid rain could be said to be: NO → NO₂ → HNO₂ + HNO₃. (Note: HNO₂ is converted to HNO₃ by catalysts in air)

 

[frezzel]

so in my assesment table, should i include NO or just use NO2 and N2O? it asks to state where they are found industrially and naturally etc.

 

[Dreamerish*~]

so in my assesment table, should i include NO or just use NO2 and N2O? it asks to state where they are found industrially and naturally etc.

It depends on what your assessment is asking for. If you are writing about the oxides of nitrogen in general, then include all three. If you are writing about atmospheric pollutants or contributors of acid rain, then you can include either both NO and NO₂ or just the latter. N₂O does not directly contribute to acid rain.

N₂O is produced by nitrogenous fertilisers reacting with the bacteria in soils.

The natural sourse of NO is lightning, and the industrial source is combustion in power stations and vehicles. Both these cases provide the high temperatures that are needed for the following reaction to occur: N₂ + 2O₂ → 2NO₂.

The only source of NO₂ is the NO produced from the above sources reacting with atmospheric oxygen: 2NO + O₂ → 2NO₂.

 

[frezzel]

Sorry, i have another question. How does N2O contribute to atmospheric polution? The question in the assessment asks to state the reasons for concern about the release of oxides of nitrogen into the environment. What is the reason for concern for N2O?

 

[frezzel]

The only source of NO₂ is the NO produced from the above sources reacting with atmospheric oxygen: 2NO + O₂ [/SIZE]→ 2NO₂.

Do you mean this is the only source naturally or at all? I thought that it could be produced by combustion, welding, power plants. I'm not sure about this however so if you could clarify it would be great.

Thanks

 

[Ioup]

Do you mean this is the only source naturally or at all? I thought that it could be produced by combustion, welding, power plants. I'm not sure about this however so if you could clarify it would be great.

Thanks

I think what Dreamerish was saying is that there is both natural sources and industrial sources of Nitric Oxide (NO).
The equation O2(g)+N2(g)>2NO(g)
This reaction can occur in the atmosphere due to the extreme heat supplied by lightning and also in combustion, welding and power plants where extreme heat is also present.
Nitric Oxide is then converted to NO2 (Nitrogen Dioxide) by
2NO(g)+O2(g)>2NO2(g)
This is the sole reaction (at least in this syllabus..) that converts NO to NO2.
The conversion of NO to NO2 does not occur due to "extreme heat" as is the case with Oxygen and Nitrogen to form NO.
A cause of concern with N2O is that it contributes to the greenhouse effect.

 

[pLuvia]

The natural source of nitric oxide, NO, is from lightning, where atmospheric oxygen and nitrogen gases combine to form nitric oxide

O₂+N₂-->2NO

But then nitric oxide slowly reacts with oxygen to form nitrogen dioxide

2NO + O₂--> 2NO₂

Which NO, and NO₂ can be formed from combustion in power stations and from vehicles.

 

[frezzel]

thanks everyone for you help!!!