What is one difference between mixtures and pure substances?

Answer 1

One key difference between mixtures and pure substances is that pure substances have a uniform and definite composition, meaning they consist of only one type of particle (either atoms or molecules) throughout. In contrast, mixtures contain two or more different substances that are physically combined, and they can vary in composition and properties. For example, a pure substance could be pure water (H₂O), while a mixture could be saltwater, which contains both salt and water in varying amounts.