We know that water is a transparent liquid without color or taste, and at the same time it is solid and gaseous. Ice and snow are also water. And in the air there is always water in the form of steam.
Then the water can be in nature in three states: liquid, gas (vapor, fog) and solid (ice, snow, hail, frost).
The state of the water depends on the temperature. If the street is warm, then the water is liquid. In frost, water freezes and turns to ice. And when heated, it evaporates and turns into water vapor.
In this case, the distance between the water molecules changes. The molecules are located very close in solid water. In liquid water they are more separated, and in gaseous water they are far away.
The transformation of liquid water into ice occurs at a temperature below 0 degrees. This is freezing.
The ice starts to melt if the temperature is above 0 degrees. Ice melting is coming.
The conversion of liquid water into steam is evaporation. Evaporation occurs at any temperature and the water becomes completely gaseous if the temperature is higher than degrees.
Water vapor is converted into liquid water at a temperature below degrees. The process is called condensation.
Special properties of ice.
In general, solids are heavier than the same substances in a liquid state. But ice does not sink in water. If you throw a piece of ice into the water, it will float to the surface.
When it freezes, water does not behave like other substances. If the water cools, it begins to shrink. But as soon as the water temperature drops below degrees, everything changes. Ice occupies a volume greater than water, and is lighter than water.
The transformation of water and its circulation in nature.
In nature, there is a constant water cycle, called the water cycle.
The driving force of the water cycle is solar heat. The sun heats the water, and evaporates.
Most of the water vapor enters the air from the surface of the oceans and seas.
A lot of water evaporates the leaves of the plants. Tree roots absorb water from nutrients dissolved in it from the soil and nourish the trunk and leaves. The sun heats the leaves and moisture evaporates from its surface.
Water vapor rises. At an altitude of several kilometers, the air is cold. The water vapor cools there and turns into raindrops or small ice floes. This is how clouds form. The clouds come together. The water accumulated in them falls to the ground in the form of precipitation: rain or snow.
Rainwater permeates the soil and flows to the rivers, and from them it enters the seas and oceans. The cycle is closed.
Water cycle stages:
- evaporation of water;
- water vapor condensation, the formation of clouds and clouds;
- precipitation (rain or snow);
- water flows to rivers, seas, oceans.