Question

How do you calculate the pOH of HCl?

Answer 1

`pOH=14-pH`

Explanation:

You can simply find the `pH` from the concentration of `H^(+)` which is equal to:

`[H^(+)]=[HCl]_0`

Then, `pH=-log[H^(+)]`

From the water dissociation constant `k_w=[H^(+)][OH^(-)]=1.0xx10^(-14)` we can take the `-log` of both parties, we get:

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

knowing that `pH=-log[H^(+)]` and `pOH=-log[OH^(-)]`, therefore,

`pH+pOH=14=>pOH=14-pH`

Here is a video that further explains this topic:
Acids & Bases | Nature, Strength & pH Scale.