【单选题】用18mol/LH 2 SO 4 溶液和100mL容量瓶配制1.8mol/LH 2 SO 4 溶液,下列有关说法正确的是( )
A.
将10mLl8mol/LH 2 SO 4 溶液加入盛有90mL水的容量瓶中
B.
将10mLl8mol/LH 2 SO 4 溶液加入容量瓶中,加水至刻度线
C.
加水时不慎超过刻度线,倒出一些液体重新加水至刻度线
【单选题】— _____ go and see Jack. — OK [ ]
【简答题】Both classes of engines are of very similar construction. But as the higher pressure is called upon in cylinders, it has to be of more substantial construction, and is thus heavier. In general, the di...
【单选题】What do we know about the whale fall in the South China Sea?
A.
It's not the first time we've seen it.
B.
Scientists found it at a depth of 4,500 meters.
C.
This whale fall may have formed recently.
D.
It has already become a skeleton.
【简答题】( )6.Before we let him go, we asked him to promise anyone what we had said to him.A. to tell not B. not to tell C. to not tell D. not tell to
【简答题】读四幅气候资料图,回答下列各题。 小题1:关于图中四地气候特征的叙述,正确的是 A.大陆性气候特征最突出的是甲 B.海洋性气候特征最突出的是乙 C.年降水量最大的是丙 D.高温期与多雨期不一致的是丁 小题2:下列关于四种气候类型分布的叙述,正确的是 ① 甲气候类型只出现在亚洲 ② 乙气候类型分布在除南极洲以外的所有大洲 ③ 丙气候类型分布在南、北纬30°一40°的大陆西岸 ④ 丁气候类型在南美洲分...
【简答题】今有0.1mol/L Na 2 SO 4 溶液300mL,0.1mol/L MgSO 4 溶液200mL和0.1mol/L Al 2 (SO 4 ) 3 溶液100mL,这三种溶液中硫酸根离子浓度之比是 A 1︰1︰1 B 3︰2︰1 C 3︰2︰3 D 1︰1︰3
【单选题】1mol/LH2SO4溶液中,c(H+)=____mol/L
【单选题】1mol/LH 2 SO 4 溶液中H + 浓度为( )mol/L