Which outcome arises when a gasoline engine's air-fuel mixture is excessively lean during combustion?

💡 Explanation

When the air-fuel mixture is excessively lean, higher combustion temperatures occur because less fuel is available to absorb heat which increases the risk of pre-ignition. Therefore, knock and overheating result, rather than reduced power, high CO, or converter failure that involve incomplete combustion within a rich mixture.

• Which outcome occurs when compressing a gaseous reaction mixture increasing exothermicity?
• Which risk increases when fuel injection in an ultra-lean burn internal combustion engine closely approaches the theoretical Carnot efficiency limit?
• Which risk increases when lithium salts are repeatedly thermally cycled?
• Which risk increases when enriched uranium isotopes accumulate impurities?
• Which consequence results when the reversible exothermic Haber-Bosch process in a closed vessel reaches equilibrium at high temperature?
• Which consequence results when crystal defects affect carrier mobility?