下列物质中,氯元素化合价最低的是
A.Cl2
B.HCl
C.HClO
D.KClO3
答案:B
氯元素在上述四种物质中的价态分别为0、-1、+1、+5价。
Mother Teresa has ____ for the poor.
A.devoted to care
B.devoted to caring
C.been devoted to caring
D.been devoted to care
生产上常用诱杀害虫的方法有哪些?