Which of the following best explains why some mixtures cannot be classified as solutions?

• A. Because mixtures always involve chemical reactions between their components.
• B. Because all mixtures are always homogeneous.
• C. Because the components in these mixtures are not uniformly distributed at the molecular level.
• D. Because solutions only exist in solid states.

Answer: (C)

Verified step by step guidance

1. Understand the definition of a solution: a solution is a homogeneous mixture where the components are uniformly distributed at the molecular or ionic level.
2. Recognize that mixtures can be either homogeneous or heterogeneous. Homogeneous mixtures have uniform composition throughout, while heterogeneous mixtures do not.
3. Identify that some mixtures are heterogeneous because their components are not uniformly distributed at the molecular level, which means they cannot be classified as solutions.
4. Note that chemical reactions are not required for mixtures to form; mixtures can be physical combinations without chemical changes.
5. Recall that solutions can exist in various states (solid, liquid, gas), so the state of matter does not limit whether a mixture is a solution.