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    In the specification it says we must be able to 'explain the choice of suitable indicators for acid-base titrations, given the pH range of the indicator'. So this means that I won't have to memorize the pH ranges of indicators right? Also if there was a 2 mark question asking us to 'explain the choice of suitable indicators for acid-base titrations'. So what would I write to make sure I get both marks? I always right what it says in the book but I only get 1 mark for some reason :confused:

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    No you don't have to memorise the pH ranges, (i don't know what board this is) but they will give you a few indicators and you will be asked to say which is best. You would have to check with the mark scheme to see what the 2 marks are given for, but something along the lines of the equivalence point matches the pH range of the indicator should suffice.
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    (Original post by tazmaniac97)
    In the specification it says we must be able to 'explain the choice of suitable indicators for acid-base titrations, given the pH range of the indicator'. So this means that I won't have to memorize the pH ranges of indicators right? Also if there was a 2 mark question asking us to 'explain the choice of suitable indicators for acid-base titrations'. So what would I write to make sure I get both marks? I always right what it says in the book but I only get 1 mark for some reason :confused:

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    You get the pH ranges in a data booklet usually which you get in the exam (for Edexcel), or they will quote you a bunch in the question in the exam. To get the second mark, you could say that:

    "Because the pH range of the indicator is within the vertical region of rapid pH change in the acid-base titration, you will see a colour change from X to Y at the end point of the titration."

    So try mentioning the fact that you will see a colour change at the end point of the titration with a specific indicator to get the second mark
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    (Original post by Acruzen)
    No you don't have to memorise the pH ranges, (i don't know what board this is) but they will give you a few indicators and you will be asked to say which is best. You would have to check with the mark scheme to see what the 2 marks are given for, but something along the lines of the equivalence point matches the pH range of the indicator should suffice.
    I do OCR. That's a relief- one less thing I have to memorize I tried finding the mark scheme, but the paper the question was in was a 2005 paper and I can't seem to find the old specification stuff.
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    (Original post by AtomicMan)
    You get the pH ranges in a data booklet usually which you get in the exam (for Edexcel), or they will quote you a bunch in the question in the exam. To get the second mark, you could say that:

    "Because the pH range of the indicator is within the vertical region of rapid pH change in the acid-base titration, you will see a colour change from X to Y at the end point of the titration."

    So try mentioning the fact that you will see a colour change at the end point of the titration with a specific indicator to get the second mark
    Oh I see, I never mention the colour change because I just assume it's too obvious to mention. Thanks
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    (Original post by tazmaniac97)
    I do OCR. That's a relief- one less thing I have to memorize I tried finding the mark scheme, but the paper the question was in was a 2005 paper and I can't seem to find the old specification stuff.
    Ah well, I do the same spec as you and if I remember correctly they only give 1 mark for that question, check though .
 
 
 
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