Answer:
A. 5.6 10⁻⁹M
Explanation:
Hello,
In this case, we should know that the pH it related with the pOH by:
[tex]pH+pOH=14[/tex]
This allows us to compute the pOH and subsequently the concentration of hydroxyl ions, [OH-], as shown below:
[tex]pOH=14-pH=14-5.75=8.25[/tex]
Thus, since pOH is mathematically defined as:
[tex]pOH=-log([OH^-])[/tex]
We finally compute [OH-] as follows:
[tex][OH^-]=10^{-pOH}=10^{-8.25}\\\\[/tex]
[tex][OH^-]=5.6x10^{-9}M[/tex]
Hence, for sure the answer is A. 5.6 10⁻⁹M
Best regards.
