What is the chemical formula for water?

The chemical formula for water is represented as H2O. This notation indicates that each molecule of water consists of two hydrogen atoms (H) and one oxygen atom (O). The "2" in H2 signifies the presence of two hydrogen atoms, which are covalently bonded to one oxygen atom, forming a stable molecular structure critical for various biological and chemical processes.

Understanding the significance of this formula extends beyond just the identification of water. It highlights the fundamental principles of chemistry, particularly regarding molecular bonding and the properties of substances. Water’s unique characteristics, such as its solvent capabilities and role in temperature regulation within ecosystems, stem directly from its molecular composition as described by H2O.

Other options do not correctly represent water; for instance, HO does not accurately account for the hydrogen atom count, while O2H and H2O2 refer to other substances (hydrogen peroxide and a nonexistent molecular structure, respectively). This emphasizes the precision required in chemical formulas for clarity and understanding within scientific communication.