water is a kind of substance & the molecules of a substance cannot move easily past each other in solid state ->  the molecules of water cannot move easily past each other in solid state  the molecules of water cannot move easily past each other in solid state & water changes into a phase where the molecules cannot move easily past each other ->  water changes into solid state  water changes into solid state & a phase change is when a substance changes from one state of matter into another state of matter & solid is a kind of state of matter ->  water undergoes a phase change  water undergoes a phase change & an example of a physical change is a phase change ->  water undergoing a phase change is an example of physical change  water undergoing a phase change is an example of physical change & if something undergoes physical change then the chemical properties of that something will remain unchanged ->  the chemical properties of water will remain unchanged  the chemical properties of water will remain unchanged & being a compound or an element is a chemical property of substances ->  water being a compound or an element will remain unchanged  water being a compound or an element will remain unchanged & water is a kind of compound -> water being a compound will remain unchanged