Question

Calculate [H3O+] and [OH−] for each of the following solutions at 25 ∘C given the pH.

pH= 11.22

Answer 1

Answer: The value of
`[H_(3)O^(+)]` is
`6.025 * 10^(-12)` M and
`[OH^(-)]` is
`1 * 10^(-14)`.

Step-by-step explanation:

pH is the negative logarithm of concentration of hydrogen ion.

It is given that pH is 11.22. So, the value of concentration of hydrogen ions is calculated as follows.

`pH = - log [H^(+)]\\11.22 = - log [H^(+)]\\conc. H^(+) = 6.025 * 10^(-12)` M

Let the value
`6.025 * 10^(-12)` is considered as equal to 0. Hence, the relation between pH and pOH value is as follows.

pH + pOH = 14

0 + pOH = 14

pOH = 14

Now, pOH is the negative logarithm of concentration of hydroxide ions.

Hence,
`[OH^(-)]` is calculated as follows.

`pOH = - log [OH^(-)]\\14 = - log [OH^(-)]\\conc. OH^(-) = 1 * 10^(-14) M`

Thus, we can conclude that the value of
`[H_(3)O^(+)]` is
`6.025 * 10^(-12)` M and
`[OH^(-)]` is
`1 * 10^(-14)`.