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问题 选择题

NA代表阿伏伽德罗常数，下列叙述正确的是（　　）

A．H2O2中加入MnO2，当产生0.1molO2时转移电子数为0.4NA

B．常温常压下，0.1mol氖气分子含有的电子数为NA

C．标准状况下，11.2L氯仿中含有C-Cl键的数目为1.5NA

D．lL1mol/L葡萄糖的水溶液含有的分子数目为1NA

答案

A、在反应2H2O2

 MnO2 
.
 
2H2O+O2↑中，产生1molO2时转移电子的物质的量为2mol，所以当产生0.1molO2时转移电子数为0.2NA，故A错误；

B、氖气分子为单原子分子，1mol氖原子核内质子数为10mol，所以0.1mol氖气分子含有的电子数为NA，故B正确；

C、氯仿（三氯甲烷）在标准状况下为液体，Vm=22.4L/mol必须使用于标况下的气体，故C错误；

D、葡萄糖的水溶液含有的分子有葡萄糖分子和水分子，葡萄糖的物质的量n=C×V=1mol，所以lL1mol/L葡萄糖的水溶液含有的分子数目大于1NA，故D错误．

故选B．

完形填空

As a mother, I have been blessed. I have a nice, smart, good-looking son named Alan. About a month ago, there was an assembly (集会) about seat belt safety 36 at Alan’s high school. One of the presenters in this program, Kathy Hezlep, had 37 her son in a horrible car crash the year before.

When Kathy was 38 asked to speak at this assembly, she was reluctant (不情愿的). Her son’s 39 had been extremely hard on her. She often felt helpless and discouraged, and she wasn’t sure how she could 40 a difference by speaking to this group.

But at last she 41 to talk to the students in the school. Kathy spoke about how 42 it had been since the loss of her son. She spoke 43 from her heart and 44 son took her words straight into his heart.

One day, the worst nightmare came. The 45 told me my son had been driving down a curving road and lost 46 of the car. When I was taken to the scene of the 47 and saw the broken car, I felt physically 48 . I couldn’t 49 three kids had walked away from that car 50 .

When I got to the hospital, I talked to Alan about the accident. He told me that 51 of the kids had been 52 their seat belts when he started the car. But Kathy’s words about her terrible loss had 53 him so deeply that he 54 that everyone put on their shoulder and lap belts before he would leave. That is 55 had saved their lives.

小题1:. 

A．spoken

B．introduced

C．presented

D．talked小题2:. 

A．lost

B．hurt

C．saved

D．seen小题3:. 

A．again

B．first

C．then

D．even小题4:. 

A．wound

B．smile

C．life

D．death小题5:. 

A．give

B．take

C．feel

D．make小题6:. 

A．allowed

B．agreed

C．refused

D．asked小题7:. 

A．hard

B．easy

C．pleasant

D．poor小题8:. 

A．wildly

B．highly

C．directly

D．safely小题9:. 

A．the

B．his

C．her

D．my小题10:.

A．parents

B．police

C．presenter

D．kid小题11:. 

A．control

B．power

C．direction

D．sense小题12:. 

A．station

B．hospital

C．road

D．accident小题13:. 

A．sick

B．depressed

C．angry

D．ashamed小题14:. 

A．express

B．predict

C．believe

D．describe小题15:. 

A．alive

B．dead

C．wakened

D．relaxed小题16:. 

A．neither

B．one

C．none

D．either小题17:. 

A．dressing

B．wearing

C．putting

D．having小题18:. 

A．remembered

B．moved

C．punished

D．impressed小题19:. 

A．hoped

B．promised

C．insisted

D．informed小题20:.

A．it

B．what

C．that

D．who
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单项选择题

不是危重哮喘表现的是（）

A.两肺满布响亮哮鸣音

B.气急不能说话

C.胸腹部矛盾呼吸

D.奇脉

E.嗜睡
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