选C烃燃烧通式CxHy+(y/4+x)O2===xCO2+y/2H20C2H4(乙烯)CxHy+(y/4+x)O2===xCO2+y/2H20,x=2带入,所以n氧气3molC6H12(环己烷)=3(C2H4)通式×3得3CxHy+(3/4y+3x)O2==3X+3/2H20x=2带进去,得nO2=9mol因为是3mol完全燃烧=9所以1mol完全燃烧=3