由A、B、C、D、E五种溶液,其组成的阳离子有Na+、Fe3+、Ba2+、Al3

题型:问答题

问题:

由A、B、C、D、E五种溶液,其组成的阳离子有Na+、Fe3+、Ba2+、Al3+、Ag+,阴离子有NO3-、OH-、SO42-、Cl-、CO32-(在溶液中离子不重复出现).现做如下实验:

①A和E溶液显碱性,0.1mol/L的A溶液的pH小于13;

②在B溶液中逐渐加入氨水有白色沉淀生成,继续加入氨水至过量,沉淀消失;

③在C溶液中加入铁粉,溶液的质量增加;

④在D溶液中加入过量Ba(OH)2溶液,没有沉淀

(1)A是______;B是______;C是______;D是______;E是______;

(2)A溶液与D溶液混合的离子方程式:______.

考点:离子的检验
题型:问答题

Today I’d like to talk about how to become a (1) . Usually you have to start at the beginning. That is, you have to begin (2) of some sort on a local newspaper, a (3) , maybe on a small magazine -- work (4) . Now there aren’t that many organizations which have large numbers of foreign correspondents so you also have to (5) with that aim (6) . Another way of doing it is to work abroad, and work as (7) . That’s somebody who sells stories, and gets paid (8) , to newspapers and magazines and so on. And hoping to (9) that way, and eventually to be offered a (10) .
I don’t really know (11) are needed, but obviously a degree in modern languages or (12) would be very useful. But, a degree in itself probably wouldn’t (13) . It wouldn’t be enough to get you job. It wouldn’t (14) to make an editor decide to (15) . So it’s difficult to define the (16) . You’re going to need (17) and the ability to assimilate information (18) and then produce stories which (19) of the newspaper or radio or television station you (20) .

题型:问答题

相同形状、体积的木块与煤块,在空气中点燃的难易程度,取决于(  )

A.它们的密度

B.它们的着火点

C.它们是否是可燃物

D.它们与空气的接触面积

题型:问答题

防火墙发展主要经历有哪几代()

A、包过滤防火墙

B、应用代理防火墙

C、攻击检测防火墙

D、状态检测防火墙

题型:问答题

驾驶舱语音和飞行记录信息将用于().

A.判断一次事故的负责人

B.作为民事责任判决或证实操作的证据

C.判断可能导致的事故的原因

题型:问答题

安装锚杆时,用预先上好连接头的锚杆体将锚固剂送到孔底,外露0.3m时开始搅拌,20s后停止搅拌,并保持钻机推力()秒后方可开动钻机,上紧螺母,取下钻机。

A.10

B.20

C.30

D.40

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