How Would You Describe Ice?
Ice is the solid form of water, produced by freezing. Water freezes to ice and ice melts to water at 0 degrees Celsius (32 degrees Fahrenheit). Most substances shrink when they freeze, but water expands slightly when it freezes. This means that ice floats on water, and a frozen pond usually has water under the ice.
Animals and plants can live through the winter in the pond protected from the cold by the ice. It also means that water pipes can crack when the water in them thaws after freezing. The cracks are discovered when the ice melts, and water pours out of them. If water freezes in a crack in rock, the ice can eventually break the rock apart.
Because of these powerful properties, ice is very important in the processes of weathering, where rocks are broken into smaller bits, and erosion, where rocks and earth are washed or moved to other locations. The expanded molecules make ice a lot lighter than liquid water, which is why ice floats.
Water covers more than 70 percent of the Earths surface. Slightly more than two percent of the Earths water is frozen into ice; almost all of this ice is in glaciers, which are huge masses of ice. Parts of the Arctic and Antarctic continents and the tops of high mountains are always covered in ice. Snow, hailstones and frost are all forms of ice.