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    (Original post by haemo)
    It's not 'difficult' maths, it's literally just remembering an equation, what each part means and putting the values in from a question (and maybe rearranging the equation and converting measurements).

    For example:

    pV = nRT

    p is pressure, in Pa
    V is volume, in m^3
    n is moles
    R is gas constant (always given)
    T is temperature, in K

    This shows that you have to remember what each part of the formula is and the units.

    Sometimes, you have to convert between the units, such as cm^3 -> m^3 (divide by a million) or dm^3 -> m^3 (divide by 1000), nothing really difficult as long as you remember the conversions.

    As long as you put in the effort and actually try, I can't see why GCSE maths wouldn't be good enough.




    AQA?
    Yup, some of my mates have done it. Said the balancing stuff was a bit long winded
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    (Original post by HToo)
    yep aqa
    How much have your classed covered of the spec? We seem to be jumping chapters, we've done the alkenes topic in unit 2 and started energetics. Not sure if we are going at a good pace?
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    Right I have a question, what makes a metal ductile/malleable?
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    (Original post by Super199)
    How much have your classed covered of the spec? We seem to be jumping chapters, we've done the alkenes topic in unit 2 and started energetics. Not sure if we are going at a good pace?
    hold up....so have you even learnt unit 1 yet ??
    couz we have done all of unit one.. and now we are doing unit 2 on group 2 alkali earth metals and metal extraction....but tell me how much of unit one have you covered so far??
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    I have my OCR F321 Quantative and Evaluative task tomorrow

    It's a titration which should go okay but i'm scared for the questions which are going to come up on the Evaluative paper ahhh
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    (Original post by HToo)
    hold up....so have you even learnt unit 1 yet ??
    couz we have done all of unit one.. and now we are doing unit 2 on group 2 alkali earth metals and metal extraction....but tell me how much of unit one have you covered so far??
    Na we have done unit 1 haha. On unit 2.
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    (Original post by ilovecake123)
    how do you do this?
    4 In which of the following electronic configurations are only two of the electrons
    unpaired?
    A 1s2 2s2
    B 1s2 2s2 2p3
    C 1s2 2s2 2p4
    D 1s2 2s2 2p5
    Well, its not A as they both have paired electrons. It isn't B because, in the 2p3, there will be one electron in the x, y, z sub shells, so 3 would be unpaired. D is incorrect because 2 would be in the x, 2 would be in the y, and only one would be in the z sub shell. So 1 electron is unpaired. C is correct because 2p4 would result in, 2 in the x, and only 1 in the y and 1 in the z.
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    I am doing Edexcel Chemistry
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    (Original post by ellsie98)
    Okay thanks, that makes sense! But surely reducing the enthalpy change would make it easier for the reaction to take place, as it requires less energy?

    Posted from TSR Mobile
    Umm no, the energy required for the reaction to occur is unrelated to the enthalpy change, that's the activation energy


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    • You can have polar bonds in a molecule, but if it's symmetrical the molecule is non-polar overall due to the charges acting in different directions and cancelling each other out.


    I don't understand this symmetrical business. Can someone explain in terms of a tetrahedral molecule of CCl4? What does it mean charges acting in different directions?

    Thanks

    (OCR A)
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    Why is there only one element with a negative oxidation number in an oxide??


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    I'm OCR chemistry
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    (Original post by Super199)
    Right I have a question, what makes a metal ductile/malleable?
    the layers can slide over each other (due to the free electrons I think)
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    (Original post by umbz4839)
    the layers can slide over each other (due to the free electrons I think)
    Free electrons mean it conducts electricity. The layers have intermolecular forces between then which is why they slide.

    Edit: thought we were talking about graphite. For metals, malleability and ability to be made into wires is due to the atoms in the layer of the metallic bonding having an elastic nature (i.e. roll one atom over another and it will roll back, unless the "roll" is very hard in which a new permanent shape of the metal will exist)

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    (Original post by haemo)
    If you were to split CCl4 into bonds, you'd have:

    4 x C-Cl bonds

    C-Cl are polar bonds because Cl is more electronegative than C, so Cl has a stronger pull on the C electrons, meaning that the C-Cl bond is asymmetrical

    This is what I mean by asymmetrical, look at the middle image and imagine C to be the smaller + and Cl to be the larger +: http://www.nature.com/nchem/journal/...em.1808-f1.jpg

    Now, we know that C-Cl is polar, but if you imagine a C atom with four Cl atoms surrounding it, the asymmetrical shape will now look symmetrical (http://ncolonie.com/lsimages/chemistry/images/CCL4.jpg) - hence it's non polar because the charges cancel
    Thanks, I understand now!
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    Name:  ImageUploadedByStudent Room1421162125.207008.jpg
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Size:  116.4 KB

    Guys if possible can you help me with this question pls as I have no idea how to do it😱😱😱. I have done part a but can't do part b. 😄😢


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    please give advice on how to study for Edexcel IAL chemistry, to get an A. Thanks
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    (Original post by A84)
    please give advice on how to study for Edexcel IAL chemistry, to get an A. Thanks
    Work Bloody Hard!
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    AQA AS CHEM (:


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    (Original post by A84)
    please give advice on how to study for Edexcel IAL chemistry, to get an A. Thanks
    Flashcards. Lots and lots of flashcards...
 
 
 
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