过氧化氢的俗称为()
A.臭氧
B.过氧乙酸
C.二氧化氯
D.双氧水
E.环氧乙烷
参考答案:D
解析:双氧水即过氧化氢,分子式为H2O2,属过氧化物类消毒剂。
.
---Though I met with one difficulty after another, I _____ to get through with it.
--Congratulations to you!
A.hoped
B.tired
C.wanted
D.managed
由金属型材料的无退让性所引起的铸件的凝固收缩特点。