选项
物质
杂质(少量)
试剂及操作方法
A
CuO
碳粉
高温灼烧
B
KNO3溶液
BaCl2
滴加适量K2SO4溶液,过滤
C
NaOH溶液
Na2CO3
加入稀盐酸至无气体产生为止
D
H2
水蒸气
缓缓通过装有足量的氢氧化钠固体的干燥管
A:A
B:B
C:C
D:D
75,3,74,3,73,3,____,____。
听第一篇短文,回答小题。请根据短文内容,选择正确答案,完成信息记录表。
A Day Out
When and where to go
They will go to Sunshine Park ⑴ .
How to go
They will go there by ⑵ .
What to do
They will ⑶ in the morning and boat in the lake in the afternoon.
They will have a picnic in the park.
判断.
把单位“1”分成8份,表示这样的3份的数是 38 .