# Question #702e2

##### 1 Answer

Aug 3, 2017

#### Explanation:

We're asked to find the hydroxide ion concentration

To do this, we can use the equation

#"pOH" = -log["OH"^- ]#

But rearrange it to solve for

#ul(["OH"^- ] = 10^(-"pOH")#

We're given that

#["OH"^- ] = 10^(-11.25) = color(red)(ulbar(|stackrel(" ")(" "5.6xx10^-12color(white)(l)M" ")|)#

Since the **two decimal places**, the hydroxide ion concentration has **two significant figures**.