A mixture is a combination of two or more substances that are physically combined together without undergoing a chemical reaction, meaning they retain their individual properties and can be separated again. Key points about mixtures:No chemical change: Mixtures are formed by physically mixing substances, not by chemical reactions. Individual properties retained: The components of a mixture maintain their own unique characteristics. Can be separated: Mixtures can be separated using physical methods like filtration, distillation, or evaporation. There are two main types of mixtures: homogeneous and heterogeneous. In a homogeneous mixture, the components are evenly distributed throughout, so it appears uniform. In a heterogeneous mixture, the components are visibly distinct and not uniformly distributed.