Anomaly of Water

Anomaly of water is a perfect design of the Creator between water volume expansion and shrinkage. On high school we were learn physics lessons about the expansion. The nature of all substances expand when heated is, the dimensions of length, area, or volume will be increased.

That is because each object is composed of particles that moves. If the object getting hotter, then the particles that content in the object also has a greater energy to move faster. Because the movement is faster, these particles require a larger space, then there was an expansion. Even if it is hot enough, that matter of object will be changed to a more free movement phase. An example from solid to liquid or from liquid to gas.
Increasing volume without mass accretion makes the density of objects decreases. For liquid and gas, a  smaller density substance will fill the of the upper section, the greater density will sink to the bottom section of the container.

So even water. If water is heated in the pan, the heat water will rise to the surface. While the cooler becomes heavier and sinks to the bottom of the pan. That's also what we learned on the subject of convection currents.

So why ice cubes float on the glass? Why icebergs float on the surface of the sea? Why in four seasons country, the top layer of the lake becomes solid, while in the depths of the lake remain liquid at the winter?

This is the anomaly of water. Water, like most other materials, will expand when heated and contract when cooled. Unless the temperature of 0 degree Celcius to 4 degree Celcius. Between these temperatures the properties of water act for the opposite, it will expand when heated and shrink when cooled. This resulted in heaviest water in 4 degree temperatures, which is at the bottom has a temperature of 4 degree. And it's not possible to freezing in that conditions, because if it is smaller than it, it will be pushed to the surface. Very beneficial for a variety of organisms that live in the water, because there is not much that can survive at temperatures below 4 degree. Or in freezing area. Then what will happens when water freezes from the bottom? There will be no ogranism alive instead.
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