Why Use Distilled Water in Enzyme Reactions?

[lha08]

Homework Statement

I have a lab tomorrow and it says it my lab book, and it says to add distilled water to a reaction consisting of the substrate then another one with the enzyme...i don't get it what's the purpose of distilled water...i really don't understand.
Thanks..

Homework Equations

The Attempt at a Solution

 

[epenguin]

Your description of what you have to do is so vague frankly I don't think anyone can tell you from that.