工业上从海水中提取单质溴可采用如下方法: (1)向海水中通入Cl2,将海水中的溴

题型:填空题

问题:

工业上从海水中提取单质溴可采用如下方法:

(1)向海水中通入Cl2,将海水中的溴化物氧化,其离子方程式为______________________。

(2)向上述混合液中吹入热空气,将生成的溴蒸气吹出,用纯碱溶液吸收,其化学方程式为__________________。

(3)将(2)所得溶液用H2SO4酸化,使NaBr,NaBrO3中的溴转化为单质溴,再用有机溶剂提取溴,还可得到副产品Na2SO4。这一过程可用化学方程式表示为___________________。

(4)这样得到的溴中还混有少量的Cl2,除去的方法是_________________。

考点:海水资源的综合利用
题型:填空题

胆囊癌的预后与分期有关,根据Nevin分期,侵犯胆囊壁全层属于()。

A.Ⅰ期

B.Ⅱ期

C.Ⅲ期

D.Ⅳ期

E.Ⅴ期

题型:填空题

More and more residences, businesses, and even government agencies are using telephone answering machines to take messages or give information or instructions. Sometimes these machines give (1) instructions, or play messages that are difficult to understand. If you (2) telephone calls, you need to be ready to respond when you get a (3)

The most common machine is the (4) used in residence. If you call a home (5) there is a telephone answering machine (6) you will hear several rings and then a recorded message that (7) says something like this: "Hello. We can’t come to the (8) right now. If you want us to call you back, please leave your name and number after the beep." Then you will hear a "beep", (9) is a brief, high-pitched (10) . After the beep, you can say who you are, whom you want to speak to, and what number the person should call to (11) you, or you can leave a (12) . Some telephone answering machines record for only 20 or 30 seconds after the beep, (13) you must respond quickly.

Some large businesses and government agencies are using telephone answering machines to provide information on (14) about which they receive a large volume of (15) . Generally speaking, using these systems (16) you to have a touch-tone phone ( a phone with buttons rather than a rotary dial). The voice on the machine will tell you to (17) a certain button on your telephone if you want information on Topic A, another button for Topic B, and so on. You listen (18) you hear the topic you want to learn about, and then you push the (19) button. Immediately after making your (20) , you will hear a recorded message on the topic.

5()

A.impossibly

B.hardly

C.always

D.usually

题型:填空题

在高增长的市场中占有高份额的产品称为( )。

A.明星产品
B.金牛产品
C.问号产品
D.瘦狗产品

题型:填空题

手种牵牛花,接连有三四年了.水门汀地没法下种,种在十来个瓦盆里.泥是今年又明年反复用着的,无从取得新的泥来加入,曾与铁路轨道旁种地的那个北方人商量,愿出钱向他买一点儿,他不肯.从城隍庙的花店里买了一包过磷酸骨粉,搀和在每一盆泥里,这算代替了新泥.*

根据作者的经验,下面说法不正确的一项是 ()

A.起头一批牵牛花花蕾开不出来

B.后来牵牛花的发育更见旺盛

C.牵牛花新的叶蔓比近根部的肥大

D.起头一批牵牛花花蕾会更加茂盛

题型:填空题

以下程序运行后,单击命令按钮,窗体显示的结果是 ______。 Private Function p1(x As Integer,y As Integel,z As Integer)p1=2*x+y+3*z End Function Private Function p2(x As Integer,y As Integer,z As Integer)p2=p1(2,y,x)+x End Function Private SubCommandl_Click()Dim a As IntegerDim b As IntegerDim c As Integera=2:b=3:c=4Print p2(c,b,A) End Sub

A.19

B.21

C.22

D.23

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