What is the chemical formula for water?

Water is one of the most essential compounds for life and is represented by the chemical formula H₂O. This means that each molecule of water consists of two hydrogen (H) atoms covalently bonded to one oxygen (O) atom. The molecule has a bent structure with an angle of about 104.5°, giving it a polar nature. The polarity of water allows it to form hydrogen bonds, which are responsible for many of its unique properties, including high surface tension, high boiling and melting points, and excellent solvent abilities.

The hydrogen and oxygen atoms share electrons to form covalent bonds, creating a stable molecule. Oxygen is more electronegative than hydrogen, which means it attracts electrons more strongly. This uneven electron distribution creates a partial positive charge on the hydrogen atoms and a partial negative charge on the oxygen atom. This polarity allows water to dissolve many ionic and polar substances, earning it the title of the “universal solvent.”

Other options in the question are unrelated compounds. NaAlO₂ is sodium aluminate, Al₂O₃ is aluminum oxide, and CaSiO₃ is calcium silicate. None of these are related to water or its essential functions in nature.

Water is vital for all biological processes, such as digestion, nutrient transport, and temperature regulation in living organisms. It also plays a key role in chemical reactions, including hydrolysis and acid-base reactions, in both nature and laboratory chemistry.

In summary, the chemical formula for water is H₂O, representing two hydrogen atoms bonded to one oxygen atom. Understanding this basic formula is fundamental in chemistry, biology, and everyday science, helping students grasp molecular structure, polarity, and the essential role of water in life and chemical processes.