posted by Katelynn .
Determine the pH of 0.18M NH4Cl.
how to find the number of moles of water in the sample
Katelynn--I answered this question at one of your other dozen posts of the same question.
Post that are piggy-backed onto another post often are ignored. I suggest you go the top of the page, click on ask a new question, and post your question that way. And while you are at it, provide all of the information needed. The number of moles in a water sample varies with the amount of water.