Hydroxide ions (OH⁻) are negatively charged ions composed of one oxygen atom and one hydrogen atom. They play a crucial role in chemistry, particularly in acid-base reactions. When dissolved in water, hydroxide ions can increase the pH, making the solution more basic or alkaline. In nature, hydroxide ions are commonly found in substances like sodium hydroxide and potassium hydroxide. They are essential in various biological processes and industrial applications, such as water treatment and the production of soaps and detergents. Understanding hydroxide ions helps in studying chemical reactions and maintaining pH balance in different environments.