Hi Sunshine200,
to the site!
Your
Peace Lily (Spathiphyllum wallisii) has experienced stress due to whatever conditions it received before you brought it home, then having the roots separated and then being moved from soil conditions to water. Depending on where you live (whether it's winter, spring, or summer) and depending on the conditions in your home, it may take a few weeks to recover and acclimate to it's new surroundings.
Do you plan on growing it in water long term, or is the water just temporary until you can get the correct soil and a pot? Are the others that you separated in water too, or did you pot them up into soil? Do they all look like the one in your photo, or were some darker green in color?
I can't see the jar and water clearly but just be sure that the water isn't too high in the glass jar; it should be just covering the roots, not high on the stems. Place it a warm location (away from any possible cold drafts of windows and doors) and be sure to change the water every 1 to 2 weeks so that it doesn't become stagnant. Hopefully you will see an improvement in the next few weeks.
I have a few Peace Lilies and I've been thinking about dividing one of them and putting it in water but still haven't done it ... maybe I'll tackle that experiment and go divide one right now.
