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    (Original post by ThatGuyRik)
    I've never had that feel :cool:
    lol bruh

    (Original post by ozzie2)
    That feel when you get a B every past paper you do
    Ozzieeeeee, been ages

    Make sure you find out you got they questions wrong and if the mark scheme doesn't explain it properly, then ask here

    Also, perhaps you should write down on a paper your mistakes?
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    (Original post by Dinaa)
    lol bruh
    Made me lol bruh
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    (Original post by Mamoona231)
    Hay

    Can anyone help me with testing for halide ions.
    What happen's if you add the nitric acid after?
    Hi there

    The test for Halide Ions

    The test solution, is made acidic with Nitric acid and then the silver nitrate solution.

    The role of Nitric acid is the react with any carbonates to prevent the formation of the precipitate Ag2CO3, because this will mark the product (and you don't want that happening haha).

    The equation:

    2HNO3 + Na2CO3 --> 2NaNO3 + H2O + CO2

    Fluorides: No precipitate will form.

    Chlorides: White precipitate will form.
    Ag+(aq) + Cl- --> AgCl(s)

    Bromides: Cream precipitate will form.
    Ag+(aq) + Br- --> AgBr(s)

    Iodides: Pale yellow precipitate will form.
    Ag+(aq) + I- --> AgI(s)

    But you ask what happens if you add it after? Idk lol but maybe the carbonate will mask the product?

    Hope that helps a little :bigsmile:
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    (Original post by Dinaa)
    Hi there

    The test for Halide Ions

    The test solution, is made acidic with Nitric acid and then the silver nitrate solution.

    The role of Nitric acid is the react with any carbonates to prevent the formation of the precipitate Ag2CO3, because this will mark the product (and you don't want that happening haha).

    The equation:

    2HNO3 + Na2CO3 --> 2NaNO3 + H2O + CO2

    Fluorides: No precipitate will form.

    Chlorides: White precipitate will form.
    Ag+(aq) + Cl- --> AgCl(s)

    Bromides: Cream precipitate will form.
    Ag+(aq) + Br- --> AgBr(s)

    Iodides: Pale yellow precipitate will form.
    Ag+(aq) + I- --> AgI(s)

    But you ask what happens if you add it after? Idk lol but maybe the carbonate will mask the product?

    Hope that helps a little :bigsmile:
    Thanks a lot
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    (Original post by Mamoona231)
    Thanks a lot

    You're welcome :blushing:
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    (Original post by Dinaa)
    lol bruh



    Ozzieeeeee, been ages

    Make sure you find out you got they questions wrong and if the mark scheme doesn't explain it properly, then ask here

    Also, perhaps you should write down on a paper your mistakes?
    Sup dina, how've you been?
    Yeah it's mostly those bonding Q's with like vander vaals forces and **** because I sometimes get confused by them, also the typical careless errors.
    I always write on my paper the answer and make a mental list of things I have to go over.
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    (Original post by ozzie2)
    Sup dina, how've you been?
    Yeah it's mostly those bonding Q's with like vander vaals forces and **** because I sometimes get confused by them, also the typical careless errors.
    I always write on my paper the answer and make a mental list of things I have to go over.

    wat exam board?
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    Just came across a unit 5 question which has questioned my knowledge a bit...

    So when you're working out the number of moles for a gas at r.t.p, eg. hydrogen
    are you working out the number of moles of H2 gas? or the number of moles for Hydrogen ( singular)

    think it's the former but can someone confirm?
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    (Original post by frozo123)
    Just came across a unit 5 question which has questioned my knowledge a bit...

    So when you're working out the number of moles for a gas at r.t.p, eg. hydrogen
    are you working out the number of moles of H2 gas? or the number of moles for Hydrogen ( singular)

    think it's the former but can someone confirm?
    H2


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    (Original post by frozo123)
    Just came across a unit 5 question which has questioned my knowledge a bit...

    So when you're working out the number of moles for a gas at r.t.p, eg. hydrogen
    are you working out the number of moles of H2 gas? or the number of moles for Hydrogen ( singular)

    think it's the former but can someone confirm?
    Fundamentally: Hydrogen, Nitrogen, Oxygen and the Halogens all exist as diatomic molecules so yes, It's H2 (g) Although avogadro's constant can apply to anything from atoms to molecules to tin cans. 1 mole of anything is always 6.02 x 10^23 whatever.
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    (Original post by Dinaa)
    wat exam board?
    AQA kiddo what about you?
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    has anyone done the physics empa?
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    (Original post by ozzie2)
    That feel when you get a B every past paper you do
    :console: It hurts but you can improve
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    I'm actually pissed off now. I've said this thousands of times now...:mad:

    (Original post by k.wills)
    ive done bio epma if anyone wants to swap for chemistry
    (Original post by Bebo98)
    has anyone done the physics empa?
    This has been said billions of times across TSR and a few other people have said on this thread already, you're not allowed to provide answers for EMPA or ISAs AT ALL!
    That would be classed as cheating which wouldn't be fair

    You're not allowed to share answers at all or shared locked/unavailable papers.

    You do realise that exam boards like AQA are monitoring TSR so if you get caught and are identified, there is a chance of you getting disqualified

    YOU DO UNDERSTAND YOU'RE NOT ALLOWED CHEAT AND THAT COULD BE CLASSED AS CHEATING RIGHT?!!!!!!!!!!!!!!!!!!!!!!!!
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    (Original post by Feraligatr)
    :console: It hurts but you can improve
    Yeah I mean a B isn't too bad considering I literally thought I knew nothing about chemistry, but after revising I feel more confident apart from the bloody intermolecular bonding and stuff which is just so annoying. If I can get near full marks in the section B part of the paper which I really like it will bump up my grade

    Btw you done the chem empa paper? I would really like the answers
    Spoiler:
    Show
    Joking, please don't kill me
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    just started to revise properly for the chem empa tomorrow with the help of e rintoul, my anus is ready
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    Anyone here doing CEA chemistry?

    Also my practical exam is THIS FRIDAY!!!:woo::woo::woo:
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    Can anyone give me some hints on what the OCR chrmistry oxidation of alcohols coursework is like? ♥★ f323
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    To all recent

    I've just joined recently but apparently AQA and other exam boards moderate these threads so we can't talk about practicals in detail. This is a high-profile thread so they'll probably check and maybe Identify you if you've given away too much info... Other regular users on this thread may have seen them?

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    lol
 
 
 
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