问题详情:若1 mol某气态烃CxHy完全燃烧,需用3 mol O2,则 ( ) A.x = 2,y =2 B.x = 2,y =4 C.x = 3,y =6 D.2=3,y=8【回答】【*】B知识点:*烃题型:选择题