Final answer:
Water is a polar molecule because it has a bent structure with a net dipole moment due to unequal electron distribution and the higher electronegativity of oxygen compared to hydrogen.
Step-by-step explanation:
Is Water Polar or Nonpolar?.Water (H2O) is considered a polar molecule. The structure of water is bent, with two hydrogen atoms bonded to a central oxygen atom. The oxygen atom is more electronegative than the hydrogen atoms, meaning it attracts electrons more strongly. As a result, there is a distribution of charge within the molecule, with the oxygen having a partial negative charge and the hydrogens having a partial positive charge. These individual bond dipoles do not cancel out due to the V-shaped molecular geometry imposed by the two lone pairs of electrons on the oxygen. This results in a net dipole moment, pointing towards the oxygen atom, confirming its polarity.
The concept of polarity is important because it explains many of water's unique characteristics, such as its solvent capabilities, high boiling point, and the fact that ice is less dense than liquid water. The strong polarity of water molecules enables them to dissolve many ionic substances and facilitates the formation of hydrogen bonds, which are crucial for the existence of life. To visualize this, if we could draw the structure here, you would see the singular oxygen atom at the 'top' of the structure, with the two hydrogens at a wide angle from it, not in a straight line. The unequal distribution of electrons, as well as the bent molecular shape, results in a molecule with a permanent dipole and characteristic polarity.