【简答题】下列仪器常用于实验室制取气体 回答: (1)d仪器的名称是 . (2)用高锰酸钾制氧气并使反应发生,现有铁架台(带铁夹)和试管,还应从上图中选择仪器 (填序号),该反应的基本类型是 . (3)采用排水法收集氧气,上述实验结束时要先将导管从水槽中取出,再熄灭酒精灯,其目的是 . (4)用仪器b和d组装成气体发生装置,为防止气体从长颈漏斗逸出,加液体时,应 . (5)实验室还可用双氧水和二氧化锰制取氧...
【多选题】薄层色谱的显色方法有?
B.
紫外灯下观察有无暗斑或荧光斑点,并记录其颜色、位置及强弱
C.
有紫外吸收物质,在紫外灯下,观察整个薄层板的颜色
【多选题】The assignment for this week is:
A.
To watch the movie Shakespeare in Love this weekend.
B.
To listen to English songs every day.
C.
To finish the exercises 3, 6, 7, 10, 11.
D.
To do nothing but sleep.
【单选题】利用个人理财业务从事洗钱活动需追究相关责任人的( )。
【多选题】The assignment for this week is:
A.
Finish listening to the audio on Xuexitong.
B.
Review the words and expressions of unit 3.
C.
Preview the words and expressions of unit 6.
【多选题】已经成型并拆模的混凝土构件,内部纵向受力钢筋有露筋的现象属于严重质量缺陷。
【多选题】The assignment for this week is:
C.
Watch an English movie during the holiday.
D.
Finish exercises 4, 5, 7, 8 of Unit 1 Passage
【多选题】The assignment for this week is:
D.
To finish the exercises 3, 6, 7, 10, 11.
【单选题】对于一个成熟期的企业,下列说法不正确的是( )