PH: product of concentration of H+ and OH-

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The equation \([H^+][OH^-]=10^{-14}\) is a fundamental principle of water chemistry, indicating that the product of hydrogen and hydroxide ion concentrations remains constant at standard conditions. While the pH of pure water is 7, the relationship between pH and pOH is expressed as pH + pOH = 14. This means that both pH and pOH are equal at 7 in pure water. The logarithmic relationship shows that \(-\log([H^+][OH^-])=14\) is valid across all solutions, regardless of acidity or basicity. Understanding this principle clarifies the behavior of acids and bases in aqueous solutions.
amcavoy
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Why is the following true?:

\left[H^+\right]\left[OH^-\right]=10^{-14}

It seems like they would cancel out (equal 10-7 instead). Thanks for your help.
 
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What substance are you talking about? pH depends on many factors and you give none. How ever if you are talking about water at standard conditions then it does indeed cancel out to 10^-7.
 
It does not equal 10^{-7}.

The pH of water is 7, and so is the pOH.

pH+pOH=7+7=14

-log[H^+]-log[OH^-]=14

-log([H^+][OH^-])=14

log([H^+][OH^-])=-14

Exponentiating both sides in base 10 gives you the result in the opening post. That result holds true no matter how acidic or how basic your solution gets.
 
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Ok thanks. I didn't realize it was for water when I looked at it.
 
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