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    Hi, we've just covered most of the alkanes topic in Chem Unit 1 AQA AS. I've got a couple of questions, which I would be grateful if someone could help solve.

    What factors cause photochemical smog? We were asked to do this for homework, yet we haven't been taught. I could hazard a guess that it's something to do with particulates and gaseous emissions maybe? Could anyone help with this please? :confused:

    Also for acid rain, we were told that it's only the sulphuric acid (from sulphur dioxide which causes it), but isn't it also carbon dioxide and nitrogen dioxide contributing as well? Is Carbon Dioxide a GHG just because it forms carbonic acid in water (or is it more complicated? :rolleyes:)

    Thanks
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    (Original post by MedicalMayhem)
    Hi, we've just covered most of the alkanes topic in Chem Unit 1 AQA AS. I've got a couple of questions, which I would be grateful if someone could help solve.

    What factors cause photochemical smog? We were asked to do this for homework, yet we haven't been taught. I could hazard a guess that it's something to do with particulates and gaseous emissions maybe? Could anyone help with this please? :confused:

    Also for acid rain, we were told that it's only the sulphuric acid (from sulphur dioxide which causes it), but isn't it also carbon dioxide and nitrogen dioxide contributing as well? Is Carbon Dioxide a GHG just because it forms carbonic acid in water (or is it more complicated? :rolleyes:)

    Thanks
    Analyse the term:

    photo = light
    chemical = chemical,

    so it's a combination of smoke and fog as a result of light and chemicals.

    CO2 reacts with H2O to form H2CO3, carbonic acid.

    NO2 reacts with H2O to form HNO3, nitric acid, both of which also cause acid rain.

    CO2 (as well as all the other GHGs) are GHGs because they absorb infra-red radiation (a lot more than in non-GHG chemicals) within their bonds (as far as I know).
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    Also, in the catalytic converters, I've been told different things in two textbooks. I know there are two layers, the platinum-rhodium and platinum-palladium.

    The former operates reduction, and latter operates oxidation?

    And for reduction, is it 2CO + 2NO -> N2 + CO2, or is it 2NO -> N2 + O2? As one book says that the NOx is reduced to form nitrogen and oxygen, whereas the otherone says that the nitrogen oxide reacts with other gases to form less harmful products. So which is correct?
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    (Original post by thegodofgod)
    Analyse the term:

    photo = light
    chemical = chemical,

    so it's a combination of smoke and fog as a result of light and chemicals.

    CO2 reacts with H2O to form H2CO3, carbonic acid.

    NO2 reacts with H2O to form HNO3, nitric acid, both of which also cause acid rain.

    CO2 (as well as all the other GHGs) are GHGs because they absorb infra-red radiation (a lot more than in non-GHG chemicals) within their bonds (as far as I know).
    Ah okay, combination of smoke and fog. What is it caused by though? Particulates in the air? As I need a couple of reasons, as there are quite a few marks for this question :/

    So they all contribute to acid rain then, as they are all acids right?
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    (Original post by MedicalMayhem)
    Ah okay, combination of smoke and fog. What is it caused by though? Particulates in the air? As I need a couple of reasons, as there are quite a few marks for this question :/

    So they all contribute to acid rain then, as they are all acids right?
    Smoke - exhaust gases from vehicles, particulates in the air

    Fog - standard fog
 
 
 
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