告诉你个万能公式
aCxHy+bO2=cCO2+dH2O
根据守恒
ax=c
ay=2d
2b=2c+d
令a=1
则c=x d=y/2 b=x+y/4
即CxHy+(x+0.25y)O2=xCO2+0.5yH2O