why does ice float on water?

Answer 1

Water has interesting thermal properties. When heated from 0°C, its melting point, to 4°C, it contracts and becomes more dense; most other substances expand and become less dense when heated. Conversely, when water is cooled in this temperature range, it expands. It expands greatly as it freezes; as a consequence, ice is less dense than water and floats on it.

In ice, each molecule forms the maximum number of hydrogen bonds, resulting in crystals composed of open, hexagonal columns. Because these crystals have a number of open regions and pockets, normal ice is less dense than water.

When ice melts, it is thought that the fragments of these structures fill many of the gaps that existed in the crystal lattice, making water denser than ice. This tendency is the dominant one between 0°C and 4°C, at which temperature water reaches its maximum density. Above this temperature, expansion due to the increased thermal energy of the molecules is the dominant factor, with a consequent decrease in density.

Answer 2

When water freezes, the water molecules bond to each other forming curved chains or even crystals that use up more space less efficiently. Thus the ice expands during freezing until solid and becomes less dense than water, and floats on water! If the temperature of ice is dropped even lower than freezing (say on land) it contracts like any other material such as steel. But of course at that lower temperature all the water would be frozen solid and there would be none to float on.

Answer 3

as the temperature of water drops, it begins to form a crystaline structures and turns solid. The inner structure of the crystaline formation more or less "pushes out" and expands (why ice cracks rocks). As the water expands into ice, the average density, or average weight, reduces. It floats since it weighs less that the same volume of liquid water.

Answer 4

Unlike other fluids water expands when it is frozen.
This is because the molecules in water rearrange themselves into chrystals so there is more space between them.

Because ice expands the density of ice is lower than that of water and therefore ice floats on water.

This also explains while bottles of water break in the freezer and why pieces of rock can break off when water in the cracks freezes.

Water is at its minimal volume at around 4 degrees Celcius.

Answer 5

The density of ice as compared to water is 0.92 gram per metre cube and the density of water is 1.00 gram per metre cube. Hence, as we know that any object with a density less than that of water will float in it. The same goes for ice. So it will float in water.

Answer 6

Law of floatation.

An object floats in a liquid if it displaces a volume of liquid whose weight is equal to the weight of the object.

Ice floats implies that it displaces a volume water whose weight is equal to the weight of ice.

Thereby we infer that the density of ice is less than the density of water.

Answer 7

The reason why ice is lighter than water is that a certain mass of ice occupies more space than the same mass of water.

Answer 8

ice's density is less than that of water. so it floats.

Answer 9

because it has a lesser density. putting objects of lesser density of water into the water guarantees it will always float.

Answer 10

usually things shrink at lower tempertures, but not ice. it expands, thus becoming less dense and lighter. (just 4 your knowledge, this answer was given by a 14-year old)