A、乙醇分子式为C2H6O,其(x+
-y 4
)=2+1.5-0.5=3,乙醛的分子式为C2H4O,其(x+z 2
-y 4
)=2+1-0.5=2.5,二者(x+z 2
-y 4
)值不相等,故A错误;z 2
B、乙醇分子式为C2H6O,其(x+
-y 4
)=2+1.5-0.5=3,乙烯分子式为C2H4,其(x+z 2
)=2+1=3,二者的(x+y 4
-y 4
)值相等,故B正确;z 2
C、乙烯分子式为C2H4,其(x+
)=2+1=3,乙醛的分子式为C2H4O,其(x+y 4
-y 4
)=2+1-0.5=2.5,二者(x+z 2
-y 4
)值不相等,故C错误;z 2
D、乙醇分子式为C2H6O,其(x+
-y 4
)=2+1.5-0.5=3,乙烷的(x+z 2
-y 4
)=2+1.5=3.5,(x+z 2
-y 4
)值不相等,故D错误;z 2
故选B.