Hydrogen carbonate, also known as bicarbonate, is represented by the chemical formula HCO3-. It is a negatively charged ion that consists of one hydrogen atom, one carbon atom, and three oxygen atoms. The hydrogen carbonate ion is commonly found in various substances, such as baking soda and antacids. It plays a crucial role in regulating the pH levels in the human body, acting as a buffer to maintain the acid-base balance. Furthermore, hydrogen carbonate is involved in many biological processes, including respiration and digestion.