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Explain how some solutions can have a negative pH? watch

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    It's only a 1 mark question i don't know the answer to. Can somebody pls tell what it is? Thanks in advance.

    x Heidi
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    Ok the formula for pH is - log [H+]

    Now i don't know if you take maths and have studied logs properly but if the pH is 5 then that means that 10 to the MINUS 5 = the concentration of hydrogen ions

    That would mean that if the pH is 2 then one over 10 squared (1/100) is the concentration of hydrogen ions

    Now if there is a really massive concentration of hydrogen ions then the concentration is going to be greater than 1 mol / dm3

    i.e. greater than 10 to the 0

    As soon as the concentration of hydrogen ions gets bigger than 1 mole, then the power of 10 gets bigger than 0

    That means that when you make it negative.... it's actually a negative number
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    Maths is so very bloomin useful if you take a science. Makes every single calculation so ridiculously easy (rates of reaction, titrations, concentrations, waves, molar equations & gas volumes, solubility constants, partial pressures - the list is huge of the topics that most maths students find very very easy. huge advantage eh?)...sorry, got carried away...
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    to put it simply, when [H+] > 1 PH will be negative.
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    (Original post by CrazyChemist)
    Maths is so very bloomin useful if you take a science. Makes every single calculation so ridiculously easy (rates of reaction, titrations, concentrations, waves, molar equations & gas volumes, solubility constants, partial pressures - the list is huge of the topics that most maths students find very very easy. huge advantage eh?)...sorry, got carried away...
    thanks for sharing that :rolleyes: :rofl:
 
 
 
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