For typical crude oils, approximate values...

Question 1 of 270705eccef9ebacbc34ba4d46532

For typical crude oils, approximate values for the lower flammable limit and upper flammable limit, would be in the range of _________.

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Question 1 of 27070

For typical crude oils, approximate values for the lower flammable limit and upper flammable limit, would be in the range of _________.

🔍 Key Concepts

• Flammable (explosive) range for hydrocarbons in air • Typical lower flammable limit (LFL) and upper flammable limit (UFL) values for crude-oil vapors • Realistic percentage of vapor in air needed for ignition

💭 Think About

• Think about whether crude-oil vapors will ignite at very low percentages in air, or if they require very high vapor concentrations. • Look at each option and ask: which range looks most like a realistic hydrocarbon flammable range (a narrow band near the lower single digits, or a very large band at higher percentages)? • Recall that outside the flammable range, mixtures are either too lean (not enough vapor) or too rich (too much vapor) to burn. Which option best fits that idea?

✅ Before You Answer

• Verify which ranges are physically realistic for vapor-in-air mixtures; very high percentages may not support combustion because there is not enough oxygen. • Confirm your memory of typical LFL/UFL values for common hydrocarbons (like gasoline vapors) and compare their order of magnitude to the options given. • Eliminate any ranges where both numbers are so high that normal air–vapor mixtures in cargo tanks would likely be too rich to ignite.