What I always found interesting and fascinating about water is how we can disolve solid things (like salt, sugar, etc) in it at room temperature (better at higher temperature, of course) and it then looks like the stuff just disapears!
You keep on adding more stuff to it, stir it, and it continues to disapear, until, of course, you finally star seeing some deposits at the bottom after enough is added...but, if you start heating the water, even that stuff disapers until it cools down again...
Almost like a magic trick.
eom