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Topic: computing pH  (Read 3092 times)

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Offline hamil

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computing pH
« on: October 11, 2009, 08:06:43 PM »
I read that most solutions have a pH between 0 and 14. However, if I add 1 mol of H2SO4 to 1 liter of water, I think I should have a pH of -0.3 since there are 2 H ions per H2SO4 molecule.  Is this correct? and a following question, if I add 2 moles of H2SO4 to 1 liter of water I would have -log10(2(2)) = -.602, right?? So does this mean that the pH can be less than 0 and I assume grreater than 14?


Offline AWK

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Re: computing pH
« Reply #1 on: October 12, 2009, 02:17:33 AM »
Ph range between 0 and 14 is a crude approximation. Assumption that 1 molar H2SO4 dissociates completely is also the approximation usually accepted for preliminary levels of chemistry (but this is a false assumption).
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Offline Borek

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Re: computing pH
« Reply #2 on: October 12, 2009, 03:35:33 AM »
So does this mean that the pH can be less than 0 and I assume grreater than 14?

Simply put - yes.
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