In terms of mixtures, which statement is true?

The statement that all mixtures can be separated by physical means is accurate because mixtures are composed of two or more substances that retain their individual properties. This characteristic allows the components of a mixture to be separated using various physical techniques, such as filtration, distillation, or centrifugation. For instance, if a mixture contains sand and salt, you can easily separate them by dissolving the salt in water and filtering out the sand.

The reasoning behind this ability to separate mixtures underlies the fundamental difference between mixtures and compounds. Compounds have fixed ratios and require chemical reactions to separate into their constituent elements, while mixtures do not change chemically when combined, allowing for their separation through physical processes. This principle is essential in organic chemistry laboratory techniques, where separation and purification of components are frequently practiced.