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

##### 1 Answer
Apr 27, 2017

$\left[H {O}^{-}\right] = {10}^{- 10} \cdot m o l \cdot {L}^{-} 1$.

#### Explanation:

In aqueous solution, $p H + p O H = 14$

And if $p H = 4$, then necessarily $p O H = 10$, and thus $\left[H {O}^{-}\right] = {10}^{- 10} \cdot m o l \cdot {L}^{-} 1$.