What chemical characteristic makes methane combustion generally considered cleaner than kerosene (RP-1) combustion regarding upper atmosphere pollution?

Answer

Methane tends to combust more completely, significantly reducing soot output

Methane, being a simpler molecule, combusts more completely than kerosene, resulting in a significant reduction in the output of soot (particulate matter).

What chemical characteristic makes methane combustion generally considered cleaner than kerosene (RP-1) combustion regarding upper atmosphere pollution?
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