Precipitation methods are techniques used to separate solids from a solution by inducing the formation of solid particles, known as precipitates. This process often involves adding a reagent that reacts with a dissolved substance, causing it to become insoluble and form a solid. Common examples include the addition of sodium chloride to silver nitrate solution, resulting in the formation of silver chloride precipitate. These methods are widely used in various fields, including chemistry, environmental science, and water treatment. They help in purifying substances, analyzing chemical compositions, and removing contaminants from solutions. Overall, precipitation methods are essential for effective separation and purification processes.