Final answer:
Water molecules cling together due to hydrogen bonding, an intermolecular force where the partially positive hydrogen atom of one molecule is attracted to the oxygen atom of a neighboring molecule. This is responsible for water's high surface tension, cohesion, and thermal properties.
Step-by-step explanation:
The reason for water molecules to cling together is because of hydrogen bonding. This is not to be confused with the bonds that hold the atoms together within a single water molecule, which are polar covalent bonds. Instead, hydrogen bonding is an intermolecular force that occurs between separate water molecules. In a water molecule, the oxygen atom is more electronegative than the hydrogen atom, which makes the bond polarized. As a result, the oxygen atom has a partial negative charge, while the hydrogen atom has a partial positive charge. These partial charges attract each other between different water molecules, forming a hydrogen bond where the partially positive hydrogen atom of one molecule is attracted to the oxygen atom of a nearby molecule.
Properties of water such as high surface tension, cohesion, adhesion, and high specific heat are due to these hydrogen bonds. The cohesion of water molecules contributes to water's ability to form droplets and its capillary action. High surface tension allows insects, such as water striders, to walk on the surface of water. Moreover, the thermal properties of water, such as its high specific heat and high heat of vaporization, can be attributed to the energy required to break these hydrogen bonds.