下列物质中,不能使酸性KMnO4溶液褪色的是①乙烯 ②乙烷 ③乙苯 ④乙炔
⑤二氧化硫 ⑥甲苯 ⑦苯 ⑧异戊二烯
A.②③⑥
B.②③⑤⑥⑦⑧
C.②⑤⑦
D.②⑦
答案:D
As used throughout the passage, the term "common" is closest in meaning to which of the following
A.Ordinary.
B.Shared.
C.Simple.
D.Popular.
颜色三原色的红、蓝混合,可得间色()。
A、紫色
B、红色
C、绿色
D、黄色