Question

The pH of a soft drink is determined to be 4.0. What is the `[OH^-]` of the drink?

Answer 1

`[HO^-]=10^(-10)*mol*L^-1`.

Explanation:

In aqueous solution, `pH+pOH=14`

And if `pH=4`, then necessarily `pOH=10`, and thus `[HO^-]=10^(-10)*mol*L^-1`.