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    At 25 oC, pH = 7.00 since at that temperature, [H+] = 1.00 x 10-7 mol dm-3.

    Why is the concentration such a nice round number? Coincidence or something I'm overlooking that I'm about to kick myself for?
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    Oh yes.. I've been doing this today in chemistry, or I might just tell you anyway..

    May I ask what level you are studying chemsitry before I delve deep into discussion?
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    (Original post by BDunlop)
    May I ask what level you are studying chemsitry before I delve deep into discussion?
    I did first year chemistry at university about 25 years ago.
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    The ionic product of water is 1x10^-14 at room temp. I mean I guess it's not going to be exactly exactly, probably 0.00000009876...moldm^-3 or something. It's so close to 1x!0^-7 though that it's a fine baseline and depending on v small temp differences I'm sure it would get incrementally close and further way from 1x10^-7.
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    (Original post by Pigster)
    At 25 oC, pH = 7.00 since at that temperature, [H+] = 1.00 x 10-7 mol dm-3.

    Why is the concentration such a nice round number? Coincidence or something I'm overlooking that I'm about to kick myself for?
    Apparently its "true" value is 0.991 x 10-14 at 298K

    http://www1.lsbu.ac.uk/water/water_dissociation.html
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    (Original post by charco)
    Apparently its "true" value is 0.991 x 10-14 at 298K
    Chemguide states it as 1.008 x 10-14 - go figure.
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    It has to be something to some amount of significant figures I suppose.

    Unless it's one of those things like at the end of Carl Sagan's 'Contact'.
 
 
 
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