问题
选择题
—Excuse me, where can l wash my hands?
—Oh, there is a_____near here. [ ]
A. post office
B. bus stop
C. restroom
D. school
答案
答案:C
—Excuse me, where can l wash my hands?
—Oh, there is a_____near here. [ ]
A. post office
B. bus stop
C. restroom
D. school
答案:C
下列除去物质中所含少量杂质的方法,错误的是[ ]
物质 | 杂质 | 除杂质的方法 | |
A. | NaCl 溶液 | 氢氧化钠 | 加入适量的稀盐酸 |
B. | CuSO4溶液 | H2SO4 | 加入适量的NaOH 溶液,充分反应后过滤 |
C. | N2 | O2 | 通过灼热的铜网 |
D. | BaSO4 | KCl | 加入足量的水,充分溶解后过滤 |