How Does Adding Water Change the Molarity of a Solution?

[oceanflavored]

Homework Statement

A student accidentally spills 227 mL of distilled water into a beaker containing 0.5 M potassium nitrate solution
A) What is the new molarity?

Homework Equations

Molarity = moles/liter

The Attempt at a Solution

I'm just REALLY confused, and I would appreciate ANY hints to start me off. I, seriously, have NO IDEA what to do.

thank you so much :)

 

[hage567]

How many moles of potassium nitrate do you have?
How does the molarity change when the volume changes after the water is added (i.e. what is the new volume)?

 

[Curious3141]

You need to know the prior volume of pot nitr. solution in the beaker.