What are the different properties of water?
What is called as the universal solvent. Water has many special properties that enable it to act as a solvent. These features are due to the polar structure of water molecule. Polarity of water molecules gives rise to hydrogen bonds.
The chemical formula of water is H2O. It means, two hydrogen atoms get attached to an oxygen atom. Since oxygen is electronegative in nature, it carries a partial negative charge. Hydrogen atoms, on the other hand, get a partial positive charge. Since the magnitude of these positive and negative charges are equal, water molecule carries no net charge.
However, these partial charges on H2O molecule attract other water molecules. This weak electrostatic attraction between H2O molecules is called HYDROGEN BOND. This hydrogen bond is responsible for many of the unusual physical properties of H2O. Some of the properties are mentioned below:
H2O is an excellent solvent:
The polarity of water molecule makes it an excellent solvent. Hydrogen bonding between water molecules and ions and between water and polar solutes in solution effectively decreases the charged substances and thereby increases their solubility.
H2O has high specific heat
Specific heat is defined as the energy required to raise the temperature of a substance by a specific amount. Unlike other liquids, water requires a relatively large energy input to raise its temperature. This large energy input is essential for plants because it helps buffer temperature fluctuations.
H2O has high latent heat of vaporization
Latent heat of vaporization is defined as the energy required to separate molecules from the liquid phase and move them into the gas phase at constant temperature – a process that occurs during transpiration. Due to high latent heat of vaporization – water enables plants to cool themselves by evaporating water from leaf surfaces.
Cohesive and adhesive properties of water
Cohesive means attraction between similar molecules and adhesive means attraction between different molecules. Due to these properties, water creates surface tension at an air-water interface. Cohesion, adhesion and surface tension give rise to a phenomenon, called CAPILLARY, the movement of H2O along a capillary tube