下列物质的变化,能通过一步化学反应完成的是( )
A.SiO2→H2SiO3
B.S→SO3
C.Al2O3→Al(OH)3
D.Cl2→NaClO
答案:D
Would you please tell me _____?[ ]
A. anything interesting
B. something interesting
C. interesting anything
D. interesting something
钢丝绳上的污垢及干固的润滑油,应用抹布和煤油清除,不准使用()清除。
A.清洁液
B.钢丝刷
C.清洁布
D.毛皮布