Using the equation pH= -log [H+], a solution with a [H+]= 10-9 M has a pH of which of the following?
10
1
9
5
Correct Answer : C
The correct answer is C. 9. The pH is determined by taking the negative logarithm (base 10) of the hydrogen ion concentration ([H+]). In this case, -log(10^(-9)) equals 9, so the pH of the solution is 9.
To find the pH of a solution with a hydrogen ion concentration ([H+]) of \(10^{-9}\) M using the equation \(pH = -\log[H^+]\):
\[ pH = -\log(10^{-9}) \]
Now, since \( \log(10^{-9}) = -9 \), the negative sign before the logarithm makes the value positive:
\[ pH = -(-9) = 9 \]
Therefore, the solution has a pH of 9
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To find the pH of a solution with a hydrogen ion concentration ([H+]) of \(10^{-9}\) M using the equation \(pH = -\log[H^+]\):
\[ pH = -\log(10^{-9}) \]
Now, since \( \log(10^{-9}) = -9 \), the negative sign before the logarithm makes the value positive:
\[ pH = -(-9) = 9 \]
Therefore, the solution has a pH of 9
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