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    sorry if this should be more off a biology question


    anyway from a lab measuring concentration of sulphonamide in a aqueous solution by UV spectroscopy for a calibration curve

    we have determined experimentally the P value for each drug need to start with calculate the log P value

    wondering how to go about this, if using a calculator which button would it be, or how you go about working it out?

    thank you
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    log P simply means the power to which you raise the number 10 to get P.

    ie: The log of 100 is 2, since if you raise 10 the power of 2, you get 100.

    There should be a "log" button on your calculator. Or maybe a log button with a subscript 10.
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    (Original post by KiraMayz)
    log P simply means the power to which you raise the number 10 to get P.

    ie: The log of 100 is 2, since if you raise 10 the power of 2, you get 100.

    There should be a "log" button on your calculator. Or maybe a log button with a subscript 10.
    i should off known that :p:

    but how do i know what the power should be?
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    (Original post by Caspa)
    i should off known that :p:

    but how do i know what the power should be?
    :confused:

    The power is what you need to calculate.
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    (Original post by KiraMayz)
    :confused:

    The power is what you need to calculate.
    sorry i got confused, wonder how do i know what the power is?

    i'm not too sure what it is for my case of results
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    (Original post by Caspa)
    sorry i got confused, wonder how do i know what the power is?

    i'm not too sure what it is for my case of results
    Taking x as the power :
    a^x = n
    therefore :

    log{a}(n} = x

    a will be base 10 by default on your calculator.
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    I'm assuming P is what you measure. So P can have any value...right?

    So, for example, in your experiment if you found the value of P to be 100, you want to find the value of log 100...right?

    In the following two equations, x is what you are trying to find, as obviously x is the value of log P.

    log P = x

    is the same as:

    10^x = P

    This is just a bit of maths. If you don't get it, just press the log button on your calculator followed by the value of P you measured and press the equals key
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    i am guessing that the absorbance would be the P value

    so say p is 0.230
    it would just be log 0.230
 
 
 

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