1molA消耗0.5molO2，1molB消耗2molO2。1mol混合C消耗1molO2根据耗氧量A...0.5...........2......B混合......1...........A...1.............0.5....BnA：nB=1:0.5=2:1
n(A)/n(B)=(4-2)/(2-1)=2/1
