# Question #8dd75

##### 2 Answers

This is dilution.

Rabigh's answer is very good, I just want to add an alternative approach to using the dilution calculations equation,

You're dealing with **0.1-M**

You can use this solution's molarity to determine the number of moles of sodium hydroxide, which *is equal to* the number of moles of *before* adding water

When you add the *remains unchanged*; the only thing that changes is the volume of the solution, which implies that the concentration of

Think of it like this: *same number of moles*, **twice** the volume **half** the initial concentration

Use this concentration to determine pOH

Therefore, pH is equal to