What Would Happen If Ice Didn't Float?

The mere freezing of water is a miracle staggering in its significance. By all the rules of physical behavior ice should not float. Almost every substance, whether solid, liquid or gas, will shrink in volume as its temperature goes down. Water follows this rule precisely as a gas and, as a liquid, for 96 percent of the way down the temperature range to its freezing point. But at 39.2 degrees Fahrenheit something happens. As cooling continues, instead of shrinking, the water expands. The icy molecules seem to trap air molecules in their frosty structures, freezing into a solid at 32 degrees Fahrenheit, forming chunks of ice that float with about nine-tenths of the bulk submerged under the surrounding water.

If it were not for this phenomenon—this wonder of floating ice—the world's seas, lakes and rivers would slowly freeze solid, depriving the earth of its much-needed water supply. But as it is, when winter comes, ice forms and floats on the surface of bodies of water, forming an insulating skin that protects the water beneath from further freezing and so safeguards the living things there.

Water is an unusual substance. Water is a liquid which when cooled shows an abnormal behaviour. When water is cooled it contracts like a normal liquid but between 4 degree celsius to 0 degree C it expands at 4 degree C its volume is minimum and its density maximum but when it is further cooled at 0 degree C its volume becomes maximum and density minimum thus ice floats on water this phenomenon is called Anomalous Expansion. If this would have not happened the ice would not float and if it would not have floated it would have been a curse for the aquatic life of places with extreme cold climate.

It is due to this only that a layer of ice is formed at the top of the sea and stops further cooling of the sea water and the temperature remains sustainable for the aquatic life there.

It would sink to the bottom of the glass instead and eventually melt