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    (Original post by YoloSwagginz)
    You don't need every colour spec specifically states fe cu and co in ppt reactions and cu nh3 deep blue cucl4 and cocl4
    this is awesome thanks
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    (Original post by Super199)
    I dont get the E cell greater than the other one stuff

    Same with 7c.
    Do you mind explaining
    The electrode potentials can show how one thing would react with another. If one is more +ve than the other then that will be the oxiding agent and the other (the more negtaive one) will be the reducing agent. So the reaction here is that Water will reduce the Au+ ions to a solid Au. So they will be a ppt in water and not in an aqueous solution whch implies that it dissolved in water which is not the case.
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    (Original post by Bloom77)
    Someone help please
    Why do you x2 for -348 and not 158?
    Question 1biii in June 2010 paper
    Attachment 554339
    Mark scheme: http://filestore.aqa.org.uk/subjects...W-MS-JUN10.PDF


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    You require two F(g) and this produced from the equation given and this is +158
    The equation with -348 is PER F to F- and as you need 2, you need to multiply it by 2.
    Hope that helped
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    (Original post by GO97)
    like every possible colour? im more than willing to learn every colour on the spec but i dont really have a source to study them, revision guide doesnt give them all and i cant find a useful site. Do you have any recommendations?
    https://chemrevise.files.wordpress.c...ion-metals.pdf

    scroll to bottom.
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    (Original post by lahigueraxxx)
    Getting hella nervous now :/// I feel like I know everything but I feel like I'm just going to blank in the exam
    Same lol. But I really can't afford to screw up this exam after chem 4, which makes me 10x even more nervous


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    How do you do this question?

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    (Original post by SirRaza97)
    The electrode potentials can show how one thing would react with another. If one is more +ve than the other then that will be the oxiding agent and the other (the more negtaive one) will be the reducing agent. So the reaction here is that Water will reduce the Au+ ions to a solid Au. So they will be a ppt in water and not in an aqueous solution whch implies that it dissolved in water which is not the case.
    I see, but in the equation how do you know which species is the oxidising agent. Is it because itself gets reduced so Au+ goes to Au?

    And the reducing agent would be H2O because it gets oxidised to H+?
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    (Original post by YoloSwagginz)
    Its yellow
    Oh thanks. I just wrote what my teacher had told me
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    yeah this is exactly what im looking for good shout
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    (Original post by Jmedi)
    You require two F(g) and this produced from the equation given and this is +158
    The equation with -348 is PER F to F- and as you need 2, you need to multiply it by 2.
    Hope that helped
    Thank you
    It did
    But why don't you also x2 for 158 because 2 F are also produced


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    http://filestore.aqa.org.uk/subjects...5-QP-JAN13.PDF

    3c.

    why do you halve the oxygen value. I don't understand
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    (Original post by DDan123)
    Same lol. But I really can't afford to screw up this exam after chem 4, which makes me 10x even more nervous


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    Aha I knowwww, this exam is my last hope Let's hope it's better !
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    (Original post by Super199)
    I see, but in the equation how do you know which species is the oxidising agent. Is it because itself gets reduced so Au+ goes to Au?

    And the reducing agent would be H2O because it gets oxidised to H+?
    Yes exactly that
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    anyone else *****ing one for tomorrow lol
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    (Original post by jammypancake)
    anyone else *****ing one for tomorrow lol
    Yup!! Literally praying it's nothing like chem4
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    (Original post by Glavien)
    How do you do this question?

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    Posted from TSR Mobile

    Chromium equations starting from

    Cr(H2O)3(OH)3 + 3H+ -> [Cr(H2O)6 ]3+

    Cr(H2O)3(OH)3 + 3OH- -> [Cr(OH)6]3- + 3H2O
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    (Original post by Bloom77)
    Thank you
    It did
    But why don't you also x2 for 158 because 2 F are also produced


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    Yeah two moles are produced but what it's doing it giving you bond dissociation enthalpy, which is that equation, which is the enthalpy change when one mole of covalent bond is broken hence no change needed.


    Atomisation enthalpy stuff, where you would have x2 before probably is for when 1 mol of gaseous atoms is formed
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    (Original post by lahigueraxxx)
    Yup!! Literally praying it's nothing like chem4
    I swear to god though, if it's anything like chem4 I'll scream. And probably cry.
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    Do we need to know the equations for the fuel cell in alkaline conditions?
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    Another oxidation question lol
    I can't seem to do these simple ones 😭
    Thank you!

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    NH3 has no charge so that's 0
    SO4 has an oxidation state of -2
    So X + 0 -2 = 0
    Therefore, X = +2
    So is that how you get the answer?



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