Chemical tests are procedures used to identify the presence of specific substances in a sample. These tests often involve adding a reagent, which is a chemical that reacts with the target substance, producing a visible change such as a color change or precipitate. Common examples include tests for pH, glucose, and proteins. In laboratories, chemical tests are essential for various applications, including water quality testing, food safety, and medical diagnostics. They help scientists and technicians determine the composition of materials, ensuring safety and compliance with regulations. Accurate results from these tests are crucial for informed decision-making in many fields.