Importance Of Water As Solvent
Separation of Plants of Class 6
Importance of water as solvent
It is because of its property of dissolving a large number of substances that water is so essential for life. Our body cannot absorb food substances unless they are soluble in water. In the process of digestion food is reduced to simple substances that are soluble in water. They can then be dissolved in water and excreted. A number of chemical reactions occur inside our body. They all occur in the presence of water.
Plants can absorb nutrients from the soil only if they are soluble in water. Minerals from the roots and food from the leaves are transported to different parts of the plant in the form of solution in water.
Gases such as oxygen and carbon dioxide which are soluble in water are important for survival of aquatic life. Fish breathe in the oxygen dissolved in water through their gills. Aquatic plants use the carbon dioxide dissolved in water for photosynthesis. Carbon dioxide is dissolved in aerated drinks to give them their tangy tastes.
The solubility of gases in water decreases with an increase in temperature. Thus dissolved gases escape from water when it is heated. This can easily be seen by gently heating water in a pot. You will see small bubbles coming out, much before water starts boiling. These are bubbles of air dissolved in water.