Which of the following best describes gasoline?

• A. It is a pure substance.
• B. It is a mixture.
• C. It is an element.
• D. It is a compound.

Answer: (B)

Verified step by step guidance

1. Understand the definitions of the terms: A pure substance has a fixed composition and distinct properties; an element consists of only one type of atom; a compound is a pure substance made of two or more elements chemically combined; a mixture contains two or more substances physically combined, not chemically bonded.
2. Recall that gasoline is composed of many different hydrocarbons and additives, which vary in proportion depending on the source and formulation.
3. Since gasoline contains multiple components that are not chemically bonded but physically mixed, it does not have a fixed composition like a pure substance.
4. Therefore, gasoline fits the definition of a mixture rather than a pure substance, element, or compound.
5. Conclude that the best description of gasoline is that it is a mixture.