Density and temperature

We used four jars. Two filled with hot water while the other two were filled with cold. The hot water was dyed blue and the cold red. Putting a notecard on top of the jar and flipping onto it's counterpart. After removing the card separating the jars the two that had the cold water on top mixed together to form a black color. Where as the one with hot on top stayed in place showing that hot water is more dense than cold. Warm water rises, and in this case just stays where it is at. This was a very helpful visual in explaining why pools that may be warm when you dip your feet in are suddenly freezing when you jump all the way in.