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Fuels: auto-ignition (self-ignition) temperature comparison The self-ignition temperature of petrol (gasoline) compared with diesel oil is: Choose the correct option.

Difficulty: Easy

Higher
Lower
About the same
Not comparable

Correct Answer: Higher

Explanation:

Concept
Auto-ignition temperature (AIT) is the minimum temperature required for a fuel–air mixture to ignite without an external spark. Typical AIT: diesel ≈ 210°C (lower), petrol ≈ 280–450°C (higher, depending on blend).

Implication
Because petrol has a higher AIT, it is used in SI engines; diesel's lower AIT enables compression ignition.

Final Answer
Higher

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