Which term describes a fuel-air mixture with more fuel than the amount required for normal combustion?

Which term describes a fuel-air mixture with more fuel than the amount required for normal combustion?

• A. Rich mixture
• B. Lean mixture
• C. Stoichiometric mixture
• D. Equivalence ratio

Answer: (B)

Having more fuel than the amount needed for complete combustion creates a fuel-rich mixture. The amount of air that would perfectly balance the fuel is the stoichiometric ratio; when you add extra fuel beyond that, the mixture becomes rich (equivalence ratio greater than one). Lean mixtures, on the other hand, have less fuel than the stoichiometric amount and excess air (equivalence ratio less than one). So the scenario described is a rich mixture, not lean.

Having more fuel than the amount needed for complete combustion creates a fuel-rich mixture. The amount of air that would perfectly balance the fuel is the stoichiometric ratio; when you add extra fuel beyond that, the mixture becomes rich (equivalence ratio greater than one). Lean mixtures, on the other hand, have less fuel than the stoichiometric amount and excess air (equivalence ratio less than one). So the scenario described is a rich mixture, not lean.