Summary
Highlights
Water is an amazing molecule formed by one oxygen atom and two hydrogen atoms. Atoms aim to have a full outer shell of electrons. Oxygen needs eight electrons, having six, while hydrogen needs two, having one. They share electrons to form covalent bonds, making all atoms achieve a full outer shell and creating a water molecule.
Covalent bonds are represented by a single straight line. However, a water molecule should be drawn with a bent shape, not straight. This bent shape is due to the lone pairs of electrons on the oxygen atom, which repel the bonding pairs and push them closer together.
Unlike molecules like methane where bonding electrons are shared equally, in water, bonding electrons spend more time near the oxygen atom. This is because oxygen is more electronegative (electron-withdrawing). As a result, the oxygen atom becomes slightly negative (delta negative), and the hydrogen atoms become slightly positive (delta positive). This makes water a polar molecule with polar covalent bonds, which is a crucial property.