Difficulty: Easy
Correct Answer: 25
Explanation:
Introduction / Context:Smoke point is a classic indicator of kerosene burning quality. Lower aromatic content generally yields a higher smoke point, signifying a cleaner, less sooty flame. The Edeleanu process selectively extracts aromatics from kerosene using liquid sulphur dioxide at low temperature, improving combustion characteristics.
Given Data / Assumptions:
Concept / Approach:Because aromatics foster soot formation, removing them increases smoke point. Industrial and exam-style benchmarks commonly cite post-extraction smoke points in the mid-20 mm region for a previously 15 mm sample, depending on cut severity and extraction ratio. Thus, a rise to about 25 mm is a realistic and widely taught result.
Step-by-Step Solution:
Recognise that smoke point increases when aromatics are selectively reduced.From a starting 15 mm, moderate extraction generally targets mid-20s mm outcomes.Among the options, 25 matches typical improvement without being unrealistic.Verification / Alternative check:Refining texts link aromatic extraction (Edeleanu or similar) to smoke-point uplift; product specs often require >20 mm for better burning fuels, consistent with an increase to ~25 mm.
Why Other Options Are Wrong:
Common Pitfalls:Interpreting smoke point as directly measuring aromatics; it is an indirect combustion metric improved by lowering aromatics.
Final Answer:25
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