Hydrocarbon formulas: Under standard textbook conventions, the general formula CnH2n corresponds to which hydrocarbons?

Introduction / Context:Recognizing empirical formulas helps classify petroleum hydrocarbons and anticipate properties relevant to refining and product performance.

Given Data / Assumptions:

• Formula: CnH2n with n ≥ 2.
• Families under consideration: olefins (alkenes) and cycloalkanes (naphthenes).
• Open-chain versus cyclic structures are both possible.

Concept / Approach:For saturated open-chain alkanes the formula is CnH2n+2. Introducing one double bond (alkenes) or forming a single ring (cycloalkanes) reduces hydrogen count by two, giving CnH2n. Thus both alkenes and cycloalkanes share CnH2n as their general formula.

Step-by-Step Solution:

Verification / Alternative check:Examples: C6H12 can represent 1-hexene (olefin) or cyclohexane (naphthene), confirming the shared formula.

Why Other Options Are Wrong:

• Olefins only / Cycloalkanes only: Each excludes the other valid family.
• Neither: Incorrect because both match.

Common Pitfalls:Assuming a unique mapping from formula to structure; structural isomerism and rings yield multiple families with the same empirical formula.

Final Answer:Both olefins (alkenes) and cycloalkanes (naphthenes)