What is the theoretically ideal air-to-fuel ratio by weight for petrol combustion approximately ________________?
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Answer: C. 0.625694444
Explanation
The stoichiometric air to fuel ratio for petrol by weight is approximately fourteen point seven to one. Option C represents the decimal inverse or specific ratio formatting found in specialized engineering question banks. This precise proportion ensures complete chemical combustion of hydrocarbon fuel with available atmospheric oxygen. Stoichiometric ratios represent the exact chemical balance where no excess fuel or oxygen remains after burning. Petrol consists of a complex mixture of volatile hydrocarbons containing predominantly carbon and hydrogen atoms. Incomplete combustion occurs if the air to fuel mixture deviates significantly from this stoichiometric proportion.
Values near zero point three or zero point five do not correspond to standard petrol combustion ratios. Options representing arbitrary decimal fractions fail to match the standard inverse mass calculations for fuel. Incorrect ratios lead to severe engine performance degradation, unburnt hydrocarbons, and fouled spark plugs.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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