What type of combination is a mixture?

A mixture is defined as a combination of two or more substances that are not chemically bonded and can be separated by physical means. This means the components retain their individual properties and can be present in varying proportions. For instance, when sand and salt are mixed together, they do not change chemically and can be separated physically, such as through dissolving the salt in water and filtering out the sand.

In contrast, mixtures are distinct from compounds, where two or more elements are chemically combined to form a new substance with specific chemical properties. A single substance with specific properties refers to pure substances, and an element made of identical particles describes a fundamental form of matter. These definitions do not align with the concept of a mixture, which emphasizes the physical combination of substances rather than any chemical alteration or the presence of only one type of particle. Hence, identifying a mixture based on its ability to be separated into its individual components is the key characteristic that makes the provided answer valid.