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    (Original post by Studentz001)
    Does anyone know the reason for electroplating?
    Electroplating

    -Improves appearance
    -Offers a protective layer
    -Makes it cheaper - i.e you a gold-plated car would cost much less than a car made of pure gold.
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    (Original post by liv1111)
    omg!!! thank you so much
    you're welcome!

    good luck tomorrow everyone!!
    get a good nights sleep, eat some breakfast and all those other cliches, I'm sure you'll do great
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    (Original post by molly2789)
    Can anyone help me out with electroplating? I know the basics but not enough for a 6 mark question on it :/
    Hi here's a 5 mark question I did on electroplating earlier if that might help you?

    Explain how and why a copper cup would be electroplated with silver.
    The cup would act as the negative electrode, and the positive electrode should be a block of pure silver metal. The electrolyte used needs to be an ionic substance containing ions of the plating metal (silver). For example, silver nitrate solution could be used. It is important that the electrolyte is in solution so that the ions can move to carry charge. The silver ions in the electrolyte will move to the negative electrode (the cup) because they are positively charged. Here each silver ion will gain 3 electrons and be reduced to silver atoms, hence the cup will be plated with silver metal. The silver metal at the positive electrode is required to top up the solution with silver ions. Electroplating is done to coat the surface of one metal with another. In this case, it is done for decoration, to make the cup look nice, because making a pure silver cup would be too expensive.
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    (Original post by harryleavey)
    1. You will be given 2 (possibly 3) elements
    e.g Sodium (Na) and Sulphur (S) and Oxygen (O)

    2. You will be given the mass or the percentage - they both work the same way
    e.g 4.6g of Na and 3.2g of S and 6.4g of O

    3. You need to get the Mr of each element by looking at the top number on the periodic table.
    In this case Na is 23 and S is 33 and O is 16

    4. Divide the percentage or mass of each by its own Mr value
    4.6/23 = 0.2 and 3.2/33 = 0.1 and 6.4/16 = 0.4

    5. Divide this result by the lowest result just obtained.
    So the lowest result was 0.1 - So all 3 are divided by 0.1
    0.2/0.1 = 2 and 0.1/0.1 = 1 and 0.4/0.1 = 4

    6. Put these 3 values in front of the symbols
    Na2 S1 O4
    = Na2SO4
    This is the final answer
    Can you help me plzz!! How did you get 4.6 (Na) 3.2 (S) and 6.4 (O)???????

    I'm stuck :mad:
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    Have titration calculations come up in the past? I think they're in the book but i haven't really seen them in past papers and i want to know how likely it is that they will come up.
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    (Original post by Crazypaw)
    Can you help me plzz!! How did you get 4.6 (Na) 3.2 (S) and 6.4 (O)???????

    I'm stuck :mad:
    In step two they said it's an example.
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    (Original post by pollyy)
    Hi here's a 5 mark question I did on electroplating earlier if that might help you?

    Explain how and why a copper cup would be electroplated with silver.
    The cup would act as the negative electrode, and the positive electrode should be a block of pure silver metal. The electrolyte used needs to be an ionic substance containing ions of the plating metal (silver). For example, silver nitrate solution could be used. It is important that the electrolyte is in solution so that the ions can move to carry charge. The silver ions in the electrolyte will move to the negative electrode (the cup) because they are positively charged. Here each silver ion will gain 3 electrons and be reduced to silver atoms, hence the cup will be plated with silver metal. The silver metal at the positive electrode is required to top up the solution with silver ions. Electroplating is done to coat the surface of one metal with another. In this case, it is done for decoration, to make the cup look nice, because making a pure silver cup would be too expensive.
    Thank you soooo much, you're a star
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    (Original post by Hiling99)
    In step two they said it's an example.
    Ohh Okay thanks
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    has anyone thought about shape memory alloys could be on the paper?
    Can you explain the usefulness of shape memory alloys?
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    Good luck to everyone doing the C2 and C3 exam tomorrow, I hope it goes well x
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    (Original post by Hiling99)
    Have titration calculations come up in the past? I think they're in the book but i haven't really seen them in past papers and i want to know how likely it is that they will come up.
    I think there was one last year
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    (Original post by 10simmondsl)
    this sounds pretty immature but the way I remember flame test colours is "little **** sods yell penis loudly caressing rainbow balls gently"
    (Lithium crimson, sodium yellow, potassium lilac, calcium red, barium green)
    Or, alternatively:
    PoP CaR BaG LiC SoY
    Potassium - Purple,
    Calcium - Red,
    Barium - Green,
    Lithium - Crimson,
    Sodium - Yellow

    pop car bag lic soy - doesn't make a full sentence, but might be less weird if someone hears you muttering it to yourself XD
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    (Original post by Studentz001)
    Does anyone know the reason for electroplating?
    We haven't even covered it in class!! But I know it's to make things look pretty (like copper items electroplated in silver so they look better etc)
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    (Original post by TIF141)
    Or, alternatively:
    PoP CaR BaG LiC SoY
    Potassium - Purple,
    Calcium - Red,
    Barium - Green,
    Lithium - Crimson,
    Sodium - Yellow

    pop car bag lic soy - doesn't make a full sentence, but might be less weird if someone hears you muttering it to yourself XD
    You need to know that potassium gives a lilac flame though not purple
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    Ohhh, thanks I found it!
    (Original post by annalg)
    I think there was one last year
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    (Original post by pollyy)
    Haha it's okay! Good luck tomorrow and let me know if there's anything else!
    Good luck to you too!
    I am very scared that the exam will have questions on hard and soft water. I think I know the basics, but not much on how hard water is softened and purified. Could you please help me?!
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    (Original post by barbaras99)
    We haven't even covered it in class!! But I know it's to make things look pretty (like copper items electroplated in silver so they look better etc)
    Ok, thanks!
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    (Original post by Hiling99)
    Ohhh, thanks I found it!
    It's ok! I hope we get one again though cause I like calculation questions!
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    Who else is scared about the 6 mark questions?
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    can anyone help answer this, what properties make ethanol a useful solvent?
 
 
 
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