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问题 选择题

利用太阳光分解水制氢是未来解决能源危机的理想方法之一。某研究小组设计了如图所示的循环系统实现光分解水制氢（a、b、c、d均为惰性电极）。反应过程中所需的电能由太阳能光电池提供，反应体系中I2 和Fe3+ 等可循环使用。下列说法正确的是

A．电极M为光电池的正极

B．d的电极反应式为2H2O + 4e- = 4H+ + O2↑

C．光催化反应池中反应的离子方程式为2Fe3++ 2I-2Fe2+ + I2

D．若循环系统处于稳定工作状态时，电解池A中流入和流出的HI浓度分别为a mol·L-1和b mol·L-1，光催化反应生成Fe3+ 的速率为c mol·min-1，则循环系统中溶液的流量为L·mol -1

答案

答案：D

电解池的阳极阴离子放电，发生氧化反应，阴极阳离子放电，发生还原反应。从电解池A的产物可以推断出：a极是阴极，因此光电池M极是负极，故A错；因为A、B 电池串联，b、c相连，均是阳极，则d是阴极，在d电极上发生：Fe3+ +e- = Fe2+，故B错；光催化反应池中反应的离子方程式应为2Fe2+ + I22Fe3+ + 2I-，故C错；光催化反应生成I-的速率υ(I-)=υ(Fe3+)="c" mol·min－1。电解池A中消耗I－的速率应等于光催化反应池中生成I－的速率，则有：a mol·L－1×Q－b mol·L－1×Q=" c" mol·min－1即

故D正确。

单项选择题

在下面Excel 2003提供的算术运算符中，优先级最高的是 (3) 。在Excel 2000工作表编辑中有对序列数据自动填充的快速输入功能，在以下各序列数据中， (4) 不能直接利用自动填充快速输入。

A．星期一、星期二、星期三

B．第一类、第二类、第三类

C．甲、乙、丙、丁

D．mort、tue、wed
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完形填空
I was out late watching a movie with a friend in Georgetown．By the time the    ended，it was 2 a．m．We walked to my car which was     across the street．When we arrived，I noticed something strange-the doors were    ．I took a quick    of the car and was relieved to find everything undamaged,    one thing-my briefcase was gone. After a further search with my friend，I    the fact that it was gone, I considered myself incredibly    that nothing valuable was taken and nothing else in the car was    ．
The next day I    a surprising voieemail from a man．He said he had walked his dog in the morning and    a pile of papers and bills with my name all over them．I    him back immediately．He promised to   the materials back or I could pick them up．At first I asked him to send them，but then I   ．We were in the same city and plus I didn’t want to inconvenience him．Normally，it probably wouldn’t be     to go to a stranger's house to   something up，but he gave me an    so I figured I was relatively safe．
I met the man and thanked him very much．He said he would   me if he found anything else. Words could not express my    of this stranger’s kindness. I thought to myself-there’s so much goodness in the world and there are so many people who    that inner goodness through acts kindness. Though it feels good to give kindness, it feels nice to      others want to give too.
小题1:
A．partyB．movieC．meetingD．night
小题2:
A．drivenB．stoppedC．boughtD．parked
小题3:
A．unlockedB．brokenC．scratchedD．changed
小题4:
A．chargeB．attemptC．surveyD．repair
小题5:
A．rather thanB．along withC．as forD．except for
小题6:
A．declaredB．acceptedC．doubtedD．predicted
小题7:
A．anxiousB．confidentC．fortunateD．satisfactory
小题8:
A．damagedB．attackedC．guardedD．emptied
小题9:
A．tookB．gotC．madeD．met
小题10:
A．made outB．went throughC．passed downD．came across
小题11:
A．turnedB．foughtC．calledD．wrote
小题12:
A．bringB．findC．holdD．mail
小题13:
A．reconsideredB．discussedC．criticizedD．remembered
小题14:
A．honestB．proudC．smartD．true
小题15:
A．tookB．pickC．sendD．put
小题16:
A．exampleB．excuseC．orderD．address
小题17:
A．meetB．chargeC．informD．greet
小题18:
A．appreciationB．approvalC．sympathyD．satisfaction
小题19:
A．searchB．expressC．driveD．remove
小题20:
A．forceB．challengeC．helpD．realize
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