Why is water ‘polar,?

The molecular structure of water is very simple. It consists of one oxygen atom and two hydrogen atoms. Each hydrogen atom is covalently bonded to the oxygen through a shared pair of electrons. Oxygen also has two unshared pairs of electrons resulting in 4 pairs of electrons surrounding the oxygen atom, two pairs in covalent bond with hydrogen and two unshared pairs on the side of the oxygen atom. Hydrogen bonds are not as strong as covalent bonds but these are strong enough to bind the water molecules together.

Uneven distribution of electron density is what makes water ‘polar,. The molecular part which contains more electronegative oxygen atom is partially negative while the other part containing less electronegative hydrogen atom is partially positive. Another reason is because of the unequal sharing of electrons inside the molecular structure of water. Oxygen atoms have a high electronegativity compared to hydrogen atoms.

Oxygen atoms will pull the electrons closer towards itself in each bond resulting in a ‘dipole, or a charge separation across the molecule, making the oxygen atoms being slightly negative while the hydrogen atoms being positive. Oxygen atoms give an asymmetrical distribution of charge whenever the electrons pull each other. This asymmetry is what gives the molecules partial positive and negative charges. One side is positively charged while the other side is negatively charged. This partial charge is well known as ‘polarity,.

Is polarity important? Polarity is what gives other molecules and ions its ability to dissolve easily in water. They dissolve in water because only polar substances can form suitable interactions with the water molecules. Water has 2 important characteristics which greatly depend on its polarity. First is its ability to dissolve any substance and the next is the low density while in its frozen state. Polarity also helps water molecules to stick together through cohesion. Adhesion is present when the water molecules bind with molecules of other substances. These 3 process namely: polarity, adhesion and cohesion are very important for every living creature.