Which characteristic applies to all mixtures?

• A. Their components react chemically to form new substances.
• B. Their components can be separated by physical means.
• C. They are always homogeneous.
• D. They have a fixed composition.

Answer: (B)

Verified step by step guidance

1. Understand the definition of a mixture: A mixture is a combination of two or more substances where each substance retains its own chemical identity and properties.
2. Recall that in mixtures, the components do not undergo chemical reactions to form new substances; instead, they are physically combined.
3. Recognize that mixtures can be either homogeneous (uniform composition) or heterogeneous (non-uniform composition), so they are not always homogeneous.
4. Note that mixtures do not have a fixed composition; the ratio of components can vary.
5. Conclude that the key characteristic of mixtures is that their components can be separated by physical means, such as filtration, distillation, or decantation.