Difficulty: Easy
Correct Answer: 18
Explanation:
Introduction:“Straight-run” gasoline refers to the naphtha-range material obtained directly from atmospheric/vacuum distillation without catalytic or thermal conversion. The percentage varies with crude type but falls within a known range for typical crudes.
Given Data / Assumptions:
Concept / Approach:Crude assays and textbook references commonly cite straight-run gasoline yields around 10–20% by volume for many crudes, often near the mid-teens. A representative figure in exam contexts is ~18%.
Step-by-Step Solution:
Eliminate extreme values: 38% or 52% are too high for straight-run without conversion.Very low 6% is possible for some heavy crudes but not “typical.”Select the canonical representative value: 18%.Verification / Alternative check:Assay tables for medium crudes show straight-run gasoline/naphtha near the high teens by volume.
Why Other Options Are Wrong:
Common Pitfalls:Confusing the final gasoline pool (post-conversion blending) with straight-run naphtha.
Final Answer:18
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