Physical and chemical properties of water. The value of water for the life of plants.

Water is the simplest combination of oxygen and hydrogen.
As you know, the most common substance on our planet
There are three states of aggregation:
Solid (snow);
Liquid (water);
Gaseous (steam).
1. Physical properties.
• Density 1000 kg / m3 or 1000 g / l, or 1 g / ml
• Heat capacity. Large heat capacity, water sources, absorb heat in the warm season, acting as a battery in winter. Thermal conductivity is not high.
• Mobility Due to this property, various rocks are eroded and deposited.
• Thermal stability – high. Water vapor decomposes into elements only at temperatures above 1000 degrees.
• Self-cleaning.
• Chromaticity. Has a bluish color.
The color depends on the angle of incidence of sunlight, the depth of the source and on impurities.
• Transparency. With good transparency, light penetrating into the depths, creates conditions for the existence and life of organisms
Water is a universal solvent.
2. Chemical properties.
at normal temperature, water interacts with:
• With alkali and alkaline earth metals:
2Н2О + 2Na = 2NaOH + H2
• With halogens:
2H2O + 2F2 = 4HF + O2
• With salts:
Al2S3 + 6H2O = 2Al2 (OH) 3 + 3H2S.
3. The value of water for plants
Water provides moisture during evaporation to all living things and plants.
Water is directly involved in photosynthesis. Without it, plants would not absorb carbon dioxide or emit oxygen, which means that it would be impossible to breathe.
Also, water provides the flow of nutrients through the plant’s root system.
Seed germination occurs only in the presence of water.
By filling the cells, it provides the plants with elasticity, thus, the plant retains its shape.