B.電流表A(量程3A.內(nèi)阻0.01Ω)C.定值電阻R(阻值2kΩ.額定電流50mA)D.蓄電池E(電動勢略小于3V.內(nèi)阻不計)E.多用電表F.開關(guān)K1.K2.導(dǎo)線若干有一同學(xué)利用上面所給器材.進(jìn)行如下實驗操作:①首先.用多用電表進(jìn)行粗測.選用×100Ω倍率.操作方法正確.若這時刻度盤上的指針位置如圖甲所示.則測量的結(jié)果是 Ω.②為了更精確地測出此電壓表內(nèi)阻.該同學(xué)設(shè)計了如圖所示的乙.丙實驗電路.你認(rèn)為其中較合理的電路圖是 .其理由是 . 查看更多

 

題目列表(包括答案和解析)

一個四棱錐和一個三棱錐恰好可以拼接成一個三棱柱.這個四棱錐的底面為正方形,且底面邊長與各側(cè)棱長相等,這個三棱錐的底面邊長與各側(cè)棱長也都相等.設(shè)四棱錐、三棱錐、三棱柱的高分別為,,,則(  )

A.           B.                  C.              D.

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閱讀下列短文,從每題所給的A、B、C、D四個選項中,選出最佳選項。

D

The first MP4 player was born years ago. Soon many music fans were wondering how fantastic it is! If you have been into technology enough, perhaps you may have a knowledge of the MP4. If not, you do need to know something before buying one, even if you are familiar with MP3. MP3 is the CD-like disc with greater capacity. How about MP4? This small digital product will really enrich the joy from listening to music. You can even feel the “touch” of music to your soul!

Now, some similar digital products advertised as “MP4 player” are simply MP3 players, which do not play video and MPEG format and also lack other particular functions. These products confuse some buyers, as they may think the “MP4” players simply mean they can do more than MP3.

What is MP4?

It is a multimedia container. It is not only used to store digital audio and digital video streams, especially those of MPEG, but can also be used to store other data such as subtitles and pictures. As a most modern container format, it allows streaming over the Internet.

With the help of a piece of MP4 video equipment, you can change various programs such as MPEG to MP4, ASX to MP4, AVI to MP4 and so on, which can be done very quickly and easily without any effect on the sound quality. By installing DVD-MP4 software, you can transfer particular music from a DVD to an MP4 video file. It really excites your listening music experience.

Then, there is MP4 advanced and you can set your own collection of all the programs—TV shows, games, and music. You can even see movies which are still running in cinema. What else digital product could you possibly ask for?

It is suggested here that you should ______ before buying an MP4 player.

   A. first be a music fan                   B. have a knowledge of MP4

   C. get familiar with MP3               D. buy a CD-like disc

From the passage, we can see that MP4 is ______ MP3.

   A. much bigger than                      B. just as advanced as

   C. not so particular as                    D. more functional than

Which function of MP4 is NOT directly mentioned in this passage?

A.Storing digital audio and video streams.

B.Recording some movies in cinema.

C.Playing TV shows, games and movies.

D.Transferring particular music from a DVD.

From the last sentence, it’s clear that the writer tries to tell us it is ______.

A.reasonable to buy other digital products

B.impossible to buy something else

C.a(chǎn) very wise choice to buy an MP4

D.a(chǎn)n exciting experience to buy an MP3

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第二部分 閱讀理解(共兩節(jié),滿分50分)
閱讀下列短文,從每題所給的四個選項(A、B、C和D)中,選出最佳選項,并在答題卡上將該項涂黑。(共20小題;每小題2分,滿分40分)
A
Now, it’s time for some brief news items.
1 China wins women's 3,000m short track relay, S. Korea disqualified
VANCOUVER, Feb. 24 (Xinhua) -- Twice Olympic champion Wang Meng led the Chinese short track speed skating team to the top podium of women's 3,000m relay with a world record at the Vancouver Winter Games here on Wednesday, as South Korea was later disqualified. Canada took the silver, with the United States picking up the bronze. South Korea's skaters had already started waving flags in joy after crossing the line but later the juges decided Kim Min-jung had impeded(阻礙) during an exchange push.
2 Severe drought cracks Airport's runway
China Daily(2010-03-18)-- Severe drought continues to plague southwestern China's Yunnan Province.
In the provincial capital Kunming, the surface of Wu Jiaba International Airport's only runway has been fractured(斷裂的). Repairs have been going on since Tuesday. The airport is closed every day from midnight to seven-thirty in the morning. Airport authorities say the severe drought is the cause of the damage. The airport also needs to repair its plane taxiing and parking area. Chen Zhiwei, Security Dept., Kunming International Airport, said, "The drought has greatly lowered the underground water level. And this has affected the runway foundations. The damage to its surface is severe."
3 School Soldiers
Russian school students will have to do basic military training in their final year of school,
the government has decided. The lesson will include learning to fire guns, marching drills
and how to deal with a chemical, nuclear or biological attack. The activity is seen as part of
a drive toward the education of their love for their country.
4____________
Is it hard for you to get up early and get ready for classes? Some students at Winter Park High School just roll out of bed in their pajamas(睡衣)and go to class in their own bedrooms, Of course, their teachers and classmates do not see them because all their class work is on the computer. The Florida High School, the state’s only online program take classes in algebra, American government, chemistry, computer, economics, and web-page design. They also have to go to regular school to attend other classes.
1. Which country ranks fourth in the women's 3,000m short track relay according to the first news?
A. S. Korea.   B. Canada.      C. The USA.          D. Not known.
2.Which of the following is correct according to the second news?
A. The airport has been closed since Tuesday.
B. Drought caused the trouble for repairs.
C. The underground water level became lower, and that’s why the Airport's runway cracked.
D. Wu Jiaba International Airport had another runway, and flights were not really stopped during the day.
3.Why will Russian school students have basic military training?
A. To get ready for a military parade.   B. To learn to protect themselves.
C. To gain some military knowledge.    D. To develop their love for the country.
4.The news from Florida can be given a title “________”.3
A. Get up Late                         B. Online School    
C. The special pajamas             D. The popular subjects

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閱讀下面短文,掌握其大意,然后從36-55各題所給的四個選項(A、B、C和D)中,選出最佳選項,并在答題卡上將該項涂黑。

Recently, I stopped by a convenience store to get a newspaper and a bottle of drink. The young woman at the check-out counter (柜臺) said, “That’ll be five dollars __36__, please.” She then __37__ down at the paper I was __38__ and said, “I’m sick and __39__ all this negative(消極的) stuff on the front __40__. I want to read some __41__ news for a change.” She then said, “In fact, I think someone should just __42__ a Good News newspaper—a paper with wonderful, inspirational(鼓舞人心的) __43__ about people overcoming difficulty and doing good things for __44__. I’d buy one every day!” She then __45__ me for coming in and said, “Maybe we’ll get some good news,” and she laughed. She made my day.

The following day after my business appointments, I __46__ the same store again to __47__ bottled water and a piece of newspaper, but a __48__ young lady was behind the counter. As I checked out, I said, “Good afternoon,” and handed her my __49__. She said nothing — not a word, not a smile or not a gesture. She just handed me my change and __50__ a negative tone (語氣) ordered, “Next!”

It hit me right between the eyes: Two people, the same age; __51__ made me feel great, and the other, well, made me feel that I had inconvenienced(給…帶來不便) her by __52__.

Every morning, you should ask __53__ this important question: “Who do I want to be today? ‘The Grouch(不高興的人)’ or ‘The Good News Girl’”? Your answer will do great good to __54__ the joy and happiness that you will experience in your __55__.

36. A. at all                        B. in all                         C. after all                  D. all for  

37. A. stared                        B. smelled                     C. looked                   D. noticed  

38. A. burying                     B. picking                     C. finding                   D. buying 

39. A. tired of                      B. interested in               C. concerned about      D. fond of 

40. A. column                      B. edition                      C. page                      D. part  

41. A. bad                           B. good                         C. latest                      D. ugly 

42. A. collect                       B. print                         C. sell                        D. publish 

43. A. stories                       B. ideas                         C. positions                D. customers  

44. A. rewards                     B. the others                  C. others                    D. money  

45. A. praised                      B. thanked                     C. observed                D. punished  

46. A. stood by                    B. took in                      C. put out                   D. stopped by  

47. A. pick up                      B. take up                      C. bring up                 D. go up 

48. A. beautiful                    B. active                        C. different                 D. stupid  

49. A. card                          B. money                      C. dollar                     D. change  

50. A. on                             B. for                            C. through                  D. in 

51. A. one                           B. who                          C. what                      D. it  

52. A. taking off                  B. going away                C. showing up             D.coming about  

53. A. her                            B. them                         C. yourself                 D. themselves

54. A. warning                     B. determining               C. enjoying                 D. damaging 

55. A. home                         B. work                         C. study                     D. life 

 

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完形填空(共20小題;每小題1.5分,滿分30分)

閱讀下面短文,從短文后各題所給的四個選項(A、B、C和D)中,選出可以填入空白處的最佳選項,并在答題卡上將該項涂黑。

He fell in love with her at the first sight at a party. She was so outstanding while he was so  36  . At the end of the party, he invited her to have  37  with him. She was very  38  , but she promised.

Sitting in a nice coffee shop, he was too  39  to say anything. Suddenly he

said to the waiter,“Would you please give me some  40  ?” Everybody stared at him, so strange!His face turned red, but still, he  41   the salt in his coffee and drank it.

She asked him  42  ,“Why do you have this  43  ?”

He replied,“When I was a little boy, I was living near the  44  . Now every time I have the salty coffee, I always think of my childhood and my  45  .”

While saying that tears  46   his eyes. She was deeply  47  . That was a really nice talk, also a beautiful beginning of their story. Later they got  48   … And, every time she made coffee for him, she put some salt in the coffee, as she knew that’s the way he liked it.

After 40 years, he passed away, leaving her a letter which  49  :

My dearest, please forgive my lie,  the only  50   I said to you --the salty coffee. The first time we  51   I was so nervous that actually I wanted some sugar. I  52   to tell you the truth many times, but I was too afraid to do that, as I have  53   not to lie to you forever… Having you is my biggest happiness even though I have to drink the salty coffee.

Her tears  54  the letter totally wet. Someday, someone asked her,“What’s the taste of salty coffee?”She replied,“It’s  55  .”

1.A. handsome  B. pretty      C. humorous    D. ordinary

2.A. dinner          B. coffee        C. tea           D. meal

3.A. surprised       B. disappointed  C. shocked       D. ashamed

4.A. anxious         B. eager         C. nervous       D. serious

5.A. sugar           B. paper         C. salt          D. spoon

6.A. put             B. took          C. mixed         D. dipped

7.A. curiously       B. carefully     C. seriously     D. elegantly

8.A. interest        B. practice      C. hobby         D. act

9.A. city            B. village       C. sea           D. road

10.A. mother         B. family        C. hometown      D. friend

11.A. formed         B. filled        C. collected     D. appeared

12.A. touched        B. moved         C. inspired      D. encouraged

13.A. divorced       B. married       C. drunk         D. hurt

14.A. wrote          B. spoke         C. told          D. said

15.A. request        B. will          C. fact          D. lie

16.A. danced         B. dated         C. gathered      D. talked

17.A. managed        B. offered       C. tried         D. failed

18.A. promised       B. asked         C. ordered       D. persuaded

19.A. watered        B. beat          C. covered       D. made

20.A. romantic B. salty   C. sweet   D. cosy 

 

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1.D【解析】β-珠蛋白DNA探針、RNA聚合酶結(jié)合位點、大腸桿菌質(zhì)粒的化學(xué)本質(zhì)都是DNA;胰島素是蛋白質(zhì);HIV的遺傳物質(zhì)是RNA;生長素是吲哚乙酸;2,4-D是一種生長素類似物。

2.D【解析】作物“燒心”是由于缺乏如鐵、鈣等在細(xì)胞中以穩(wěn)定化合物形式存在的礦質(zhì)元素,有別于因缺水而造成的“燒苗”。

3.B【解析】疫苗的作用是在機體不患病的情況下發(fā)生免疫反應(yīng),產(chǎn)生的抗體與抗原結(jié)合,發(fā)揮免疫效應(yīng);流感病毒的遺傳物質(zhì)是單鏈的RNA,其結(jié)構(gòu)穩(wěn)定性不如天花病毒的雙鏈DNA,容易發(fā)生變異,所以流感疫苗的研究的難度較天花疫苗研究的難度大很多;正是由于流感病毒極易發(fā)生變異,所以某種特定的單克隆抗體不一定對其它的抗原起作用。

4.C【解析】生態(tài)系統(tǒng)的成分除生產(chǎn)者、消費者和分解者外,還包括了非生物的物質(zhì)和能量;生物圈的自給自足表現(xiàn)在物質(zhì)上,能量來源于太陽能;草原上的牛和羊同屬于第二營養(yǎng)級,共獲得生產(chǎn)者固定太陽能的10%~20%。

5.B【解析】考查分泌蛋白的形成和分泌過程這一知識點和圖形分析能力。蛋白質(zhì)分泌以細(xì)胞膜的外排方式實現(xiàn),所經(jīng)過的膜結(jié)構(gòu)順序為:內(nèi)質(zhì)網(wǎng)→高爾基體→細(xì)胞膜,所以結(jié)果是:內(nèi)質(zhì)網(wǎng)面積減小,高爾基體膜面積不變,細(xì)胞膜面積增加。

6.B 【解析】有機分子的特點一般滿足C四鍵、H一鍵、N三鍵原則,三聚氰胺分子中含有3個-NH2,則其余3個C、3個N形成一個六元環(huán),故三聚氰胺的結(jié)構(gòu)簡式為。。根據(jù)三聚氰胺的結(jié)構(gòu)簡式,該物質(zhì)不是高聚物,也不是氨基酸,但分子中含有不飽和鍵,在一定條件下能發(fā)生加成反應(yīng)。六元環(huán)不變且除自身外的三聚氰胺的異構(gòu)體有3種。

7.B   【解析】選項A,Na2O2中含有的陽離子為Na,陰離子為O22?,0.1mol  Na218O2中含有的陰陽離子總數(shù)為0.3NA。選項B,C2H4、C3H6的化學(xué)式均為CH2,1.4g二者含有的C原子數(shù)的物質(zhì)的量=1.4g/14g?mol-1=0.1mol,即0.1NA。選項C,0.1mol Cl2參與反應(yīng)電子轉(zhuǎn)移0.1mol。選項D,D2O為10電子微粒,18g D2O物質(zhì)的量小于1mol,含有的電子數(shù)也小于NA

8.A 【解析】選項A,ClO具有氧化性,SO2具有還原性,SO2被氧化為SO42?,ClO被還原為Cl?,正確。選項B,加入少許H時,CO32?優(yōu)先與H結(jié)合生成HCO3?。選項C,離子方程式兩邊電荷不守恒。選項D,Mg2能與電解產(chǎn)生的OH?結(jié)合生成難溶性Mg(OH)2沉淀:Mg2 + 2Cl? + 2H2O=Mg(OH)2↓+ H2↑+ Cl2↑。

9. B 【解析】加入稀H2SO4出現(xiàn)白色混濁說明一定存在Ba2,因SO32?、CO32?能與Ba2結(jié)合生成難溶物BaSO3、BaCO3,所以原溶液中不存在SO32?、CO32?。由于溶液呈電中性,剩下的一種HCO3?,一定存在。無法判斷是否含有K,所以原溶液中一定含有Ba2、HCO3?,可能含有K。溶質(zhì)可能是Ba(HCO3)2或Ba(HCO3)2和KHCO3

10.D 【解析】根據(jù)題設(shè)條件可推知A為NH4,B為OH?,C為NH3,D為H2O。NH3能與H2O反應(yīng)生成NH3?H2O。NH4為離子,不是分子,所以NH4不是非極性分子。選項D,固態(tài)H2O分子間存在氫鍵,其熔沸點高于固態(tài)H2S,與H-O和H-S鍵強弱無關(guān)。NH4Cl ,NH4水解溶液的pH<7。

11.C【解析】分析反應(yīng)①②中各元素的價態(tài)變化可知,反應(yīng)①中,SO2為還原劑,F(xiàn)e3為氧化劑,且還原性:SO2>Fe2,氧化性:Fe3>SO42?。反應(yīng)②中,F(xiàn)e2為還原劑,Cr2O72?為氧化劑,且還原性:Fe2>Cr3+ ,氧化性:Cr2O72? > Fe3。由此可見選項A、B錯誤。選項C,由于Cr2O72?具有氧化性,Na2SO3具有還原性,故Cr2O72? 能將Na2SO3氧化成Na2SO4。選項D,反應(yīng)①中Fe2(SO4)3為氧化劑,反應(yīng)②中Fe2(SO4)3為氧化產(chǎn)物。

12.C【解析】選項A,NaHS、Na2S溶液又因為有HS?、S2?的水解,使其溶液呈堿性,但S2?的水解能力大于HS?,故溶液的pH值:③>②。H2S溶液呈酸性,H2S和NaHS混合液中,由于HS?抑制的H2S的電離,故溶液的pH:④>①,4種溶液pH大小順序為:③>②>④>①。選項B,由于HS?抑制H2S的電離,所以H2S溶液中的c(H2S)小于H2S和Na2S混合液中的c(H2S)。選項C,c(Na)=0.1mol?L-1,根據(jù)物料守恒有:c(H2S) + c(HS?) + c(S2?)=0.2mol?L-1,故2c(Na)=c(H2S) + c(HS?) + c(S2?)。選項D,根據(jù)電荷守恒有:c(H) + c(Na)=c(OH?) + c(HS?) +2 c(S2?)。

13.B 【解析】設(shè)達(dá)平衡時生成SO3(g)物質(zhì)的量為2x ,則剩余SO2(g)的物質(zhì)的量為(3-2x),O2(g)(2-x),混合氣體總的物質(zhì)的量為(5-x),根據(jù)阿伏伽德羅定律有5/(5-x)=1/0.9,解得x=0.5mol,再結(jié)合熱化學(xué)方程式可知,放出的熱量為196.6kJ/2=98.3kJ。選項B,起始物質(zhì)的量改為 4mol SO2 、 3 mol O2 、2SO3 (g) 相當(dāng)于加入6mol SO2、4mol O2,n(SO2)/n(O2)=3/2,故與第一次平衡是等效平衡,兩次平衡中SO2的轉(zhuǎn)化率、SO3的體積分?jǐn)?shù)相等,故選項B正確,C錯誤。選項D,題目沒有告訴達(dá)平衡時的時間,無法計算反應(yīng)速率。

14.AD【解析】由狀態(tài)方程知溫度升高而壓強增大體積必增大,故狀態(tài)I時氣體的密度比狀態(tài)II時氣體的密度大,A正確,平衡態(tài)II的溫度比狀態(tài)I高,故狀態(tài)I時分子的平均動能比狀態(tài)II時分子的平均動能小,B錯誤,由熱力學(xué)第一定律知從狀態(tài)I到狀態(tài)II過程中溫度升高內(nèi)能變大,體積增大對外界做功,氣體要從外界吸熱,故C錯,D正確,故選AD。

15.答案:BD【解析】:在同一介質(zhì)中紅光傳播速度最大,從AB面射入到BC面射出,紅光用的時間最短,故選項A錯.由于玻璃對紅光折射率最小,對紫光的折射率最大,即紫光的偏折本領(lǐng)最大,所以彩色光帶右邊緣的色光為紅光,左邊緣的色光為紫光,且紫光的頻率比紅光的要高,當(dāng)紅光能讓某金屬板發(fā)生光電效應(yīng),紫光也一定能夠,故選項B正確.在同樣條件下做雙縫干涉實驗,波長越長,相鄰干涉條紋間距越大,而彩色光帶左邊緣的色光是紫光,其波長最短,故選項C錯.對玻璃而言,在七色光中,紅光的臨界角最大,當(dāng)∠MNB逐漸變小時,射到AC面上的光的入射角變小,且紅光入射角小得更多,故紅光最先從從AC面透出,所以選項D正確.

16、答案 D 【解析】 燒斷細(xì)線后,無論是彈簧將A+BC彈開過程,還是AB分離后,系統(tǒng)始終動量守恒、機械能守恒;彈簧將A+BC彈開過程,A+BC動量大小相等,動能跟質(zhì)量成反比,因此A+B的總動能是E/3,其中A的動能是E/6;當(dāng)時C的動能是2E/3;前3個選項都錯,可判定D正確。證明:AB分離時,B+C的總動能是5E/6,BC共速時彈性勢能最大,當(dāng)時AB+C動量大小相等,動能跟質(zhì)量成反比,因此B+C的動能是E/12,該過程B+C的動能損失就是此時的彈性勢能,因此Ep=5E/6- E/12=3E/4。

17.答案:ACD【解析】:根據(jù)波的傳播方向,可以判斷b質(zhì)點此時刻振動方向沿y軸負(fù)方向,離開平衡位置,速度正在變小,A對;由圖象可知該波的波長是4m,根據(jù)發(fā)生明顯衍射現(xiàn)象的條件判斷D正確;根據(jù),由波干涉條件知C正確;經(jīng)過0.01s即半個周期,任何質(zhì)點通過的路程都是2個振幅,即0.4m,B錯誤.

18.C【解析】從圖(甲)到圖(乙)的過程中,根據(jù)動能定理有:,所以;從拋出后到落地,根據(jù)動能定理得:,代入上式可得:。

19.答案: BC 【解析】此模型為類雙星模型,兩電荷做圓周運動的角速度相等;兩個電荷之間的庫侖力充當(dāng)各自做圓周運動的向心力,所以向心力大小相等,A錯,B對.由知,線速度大小與質(zhì)量成反比,運動半徑與質(zhì)量成反比,C對,D錯.

20.答案:ABD 【解析】天然放射性元素的半衰期與溫度改變無關(guān)。根據(jù)質(zhì)能方程計算可知D答案正確。

21.答案:.D  【解析】地球同步衛(wèi)星是指與地球自轉(zhuǎn)同步的人造衛(wèi)星,它的周期是24小時,它的軌道平面只能在赤道,軌道也是固定的,但并不是說同一赤道平面內(nèi)的、或是周期與地球自轉(zhuǎn)周期相等的就都是同步衛(wèi)星,故A、C是錯的、D是正確的;同步衛(wèi)星做圓周運動時,內(nèi)部的儀器是處于失重狀態(tài)而不是超重狀態(tài),B錯

22.答案.(1)(g+a)× (OM-ON)=(g-a)× OP    (4分)

【解析】利用紙帶分析得m1帶動m2的加速度為a ,又由牛頓第二定律得a=解得

3000;(2分)

(1分);乙圖中電流表的示數(shù)太小,誤差太大丙圖中R的阻值與電壓表阻值接近,誤差小。(3分)。

⑶實物圖連接如右圖所示:(4分)

⑷實驗步驟:

閉合K1.再閉合K,讀得電壓表示數(shù)U;再斷開K,讀得電壓表示數(shù)U.(2分)、冢V。(2分)

23.【解析】:(1)負(fù)電……(2分)∵mg =E×……(5分)

E=4(r+R)dmg/Rq…………(2分)

(2)mg+q v0B=……………(5分)    ∴v0=mg/qB…………(2分)

24.【解析】:(1)ab通過最大電流時,受力分析如圖甲,此時靜摩擦力最大,,方向沿斜面向下,由平衡條件得:

水平:

(3分)

豎直:(3分)

以上兩式聯(lián)立得出

(3分)

(2)通以最小電流時,ab受力分析如圖乙,此時ab受靜摩擦力,方向沿斜面向上,與(1)類似,由平衡條件得:(3分)

(3)當(dāng)ab中電流最小時,變阻器阻值為:(3分)

當(dāng)ab中電流最強時,變阻器阻值為:,(2分 )

為保持ab靜止,R的調(diào)節(jié)范圍為0.91~10.(1分)

25.【解析】:(1)設(shè)A物塊碰撞B物塊前后的速度分別為v1和v2,碰撞過程中動量守恒,

  代入數(shù)據(jù)得:        (4分)

(2)設(shè)A、B兩物塊碰撞前后兩物塊組成的系統(tǒng)的機械能分別為E1和E2,機械能的損失為,根據(jù)能的轉(zhuǎn)化和守恒定律:   

     %     (4分)

(3)設(shè)物塊A的初速度為v0,輪胎與冰面的動摩擦因數(shù)為µ,A物塊與B物塊碰撞前,根據(jù)動能定理:                 (3分)

碰后兩物塊共同滑動過程中根據(jù)動能定理:

         (3分)

、  及(1)、(2)得:    (2分)

設(shè)在冰面上A物塊距離B物塊為L′時,A物塊與B物塊不相撞,

則:                             (4分)

26.(15分)(1)(1)KNO3 (2分)CuSO4(2分)

(2) Na2CO3  (2分)

(3)Al3 + 3OH?=Al(OH)3↓(3分) Al(OH)3 + OH?=AlO2? + 2H2O (3分)

(4) Al3 + 3H2O Al(OH)3(膠體)+ 3H (3分)

【解析】根據(jù)實驗①可知,D中含有Cu2;根據(jù)實驗②可知C中含有Al3,E可能是KOH或NaOH,再根據(jù)③,只有B、C中含有K,故E為NaOH。根據(jù)實驗③A中含有HCO3?,故A為NaHCO3,C、D中含有SO42?,故D為CuSO4,C為KAl(SO4)2。

最后可判定B為KNO3。等物質(zhì)的量的NaHCO3與NaOH反應(yīng)生成Na2CO3和H2O。 NaOH溶液加入到KAl(SO4)2溶液中,首先是Al3與OH?反應(yīng)生成Al(OH)3,Al(OH)3沉淀又溶解在過量的NaOH溶液中:Al3 + 3OH?=Al(OH)3↓,Al(OH)3 + OH?=AlO2? + 2H2O。KAl(SO4)2中的Al3水解生成具有吸附作用的Al(OH)3膠體而凈水。

27.(14分)(1)Na2CO3 +HCl=NaHCO3 + NaCl    (3分)

(2)Cl2 + 2OH?=Cl? + ClO? + H2O (3分)

(3)①Na2O或Na2O2  (4分,每空各2分)②Na或NaOH (4分,每空各2分)

【解析】(1)根據(jù)題設(shè)條件可知,B為鹽酸,C為CO2,D為H2O,E為NaCl。

(2)根據(jù)題設(shè)條件可知B為濃鹽酸,C為Cl2。

(3)若C為O2,D、E的焰色反應(yīng)均為黃色,D、E中含有Na,含有Na的能產(chǎn)生O2的固體為Na2O2,E能與鹽酸反應(yīng)生成的氣體能使澄清石灰水變混濁,該氣體為CO2,B、E可相互轉(zhuǎn)化,故可推知B溶液為NaHCO3溶液,E為Na2CO3溶液,D為NaOH溶液。Na2O2與NaHCO3溶液反應(yīng)可分解為:2Na2O2 + 2H2O=4NaOH + O2↑,NaHCO3 + NaOH=Na2CO3 + H2O。amol NaHCO3→a mol Na2CO3,只要增加a mol Na,同時用OH? 將HCO3?轉(zhuǎn)化為CO32? ,所加物質(zhì)所產(chǎn)生的Na和OH?的物質(zhì)的量相等,才能不產(chǎn)生雜質(zhì),故X為Na2O或Na2O2,Y為Na或NaOH。

28.(16分)(1)B(2分)  銅與HNO3反應(yīng)前,應(yīng)排凈裝置內(nèi)的空氣,防止NO與O2發(fā)生反應(yīng) (2分)

(2)將C中的溶液加適量水稀釋(2分)

(3)③④⑤⑨ (3分)

(4)第二,打開a,通足量N2,排凈裝置中的空氣(2分)

(5)向下移動乙管,使甲、乙兩管液面在同一水平面上(2分)
(6)(V-11.2n)/33.6n (3分)

【解析】根據(jù)實驗?zāi)康,要求得m值,需測定出Cu與HNO3反應(yīng)生成的NO2和NO的物質(zhì)的量,為此需將產(chǎn)生的氣體首先通入裝置C中,H2O吸收NO2生成NO和HNO3,用裝置E測定出NO的體積,如果裝置中有空氣,空氣中的O2會將NO氧化成NO2導(dǎo)致實驗誤差,裝置B通入N2能將裝置中空氣趕走,防止NO被氧化,為此需要的裝置為B、C、E,裝置接口連接順序為③④⑤⑨。由于濃HNO3具有強氧化性,能將指示劑氧化而影響實驗,可加水稀釋降低其氧化性,而溶質(zhì)HNO3的量不變,便于觀察指示劑顏色變化。用裝置E測定NO的體積時,如甲的液面高于乙的液面,測出的NO體積偏小,如甲的液面低于乙的液面,測出的NO體積偏大,故應(yīng)向下移動乙管,使甲、乙兩管液面在同一水平面上,從而減少誤差。根據(jù)反應(yīng):3NO2 + 2H2O=2HNO3 + NO,混合氣體中含有NO21.5nmol,NO總的物質(zhì)的量為V/22.4mol,其中屬于Cu與HNO3反應(yīng)生成的NO為(V/22.4-n/2)mol,故M=(V/22.4-n/2):1.5n=(V-11.2n)/33.6n。

29.(15分)(1)取代(或水解)、中和反應(yīng) (2分) (2)HCOOCH3  (2分) HOCH2CHO (2分)

(3)(2分)

  (4)+ 3NaOH+ CH3COONa + 2H2O (3分)

(5) (2分) (2分)

 

【解析】A的分子式為C9H8O4,A能與醇發(fā)生酯化反應(yīng),說明A中含有-COOH,且A在NaOH溶液中發(fā)生水解生成CH3COONa,說明A中酯的官能團,該官能團與-COOH處于苯環(huán)上的鄰位,再結(jié)合A的分子式推知A的結(jié)構(gòu)簡式為,B為,由于H2CO3的酸性大于酚而小于羧酸,故在溶液中通入CO2時,只有酚的鈉鹽反應(yīng)生成D()和NaHCO3。CH3COONa與H反應(yīng)生成E(CH3COOH)。CH3COOH的同分異構(gòu)體中R中含有-CHO和-OH:HOCH2CHO,Q中含有-CHO而沒有-OH:HCOOCH3。對照結(jié)構(gòu)可知,首先用與酚羥基反應(yīng),然后再用酸性KMnO4氧化-CH3為-COOH即可得到A。

30.【解析】(1)新陳代謝是生物最本質(zhì)的特征。(2)人體內(nèi)水的來源包括:飲水、食物中的水、代謝產(chǎn)生的水,人體代謝產(chǎn)生水的途徑有:核糖體上的氨基酸脫水縮合、線粒體中的有氧呼吸等。(3)異化作用類型包括需氧型、厭氧型和兼性厭氧型,根據(jù)材料提供信息,氣性壞疽的異化作用類型為厭氧型。(4)本題考查的是細(xì)胞的選擇透過性,細(xì)胞的功能特性決定于細(xì)胞膜上的載體的種類和數(shù)量

【答案】(12分,每空各2分)(1)新陳代謝現(xiàn)象  (2) 代謝產(chǎn)生水   

氨基酸脫水縮合(或有氧呼吸)      (3)  厭氧型

(4)選擇透過性    載體蛋白 

【解析】由反應(yīng)式:CO2+C5→C32C3學(xué)科網(wǎng)(Zxxk.Com)C5+CH2O可知:一定范圍內(nèi)的CO2增加可以使細(xì)胞中C3增加;一定范圍內(nèi)的光照增強會導(dǎo)致細(xì)胞內(nèi)C5增加。甲圖信息顯示:只考慮光照的影響,光照強度為由n增加到k時,光合速率幾乎不變,而乙圖的變化應(yīng)是光照之外的其他因素引起,比如溫度等

【答案】(10分,每空各2分)(1)低、高、約等于   (2)溫度   

(3)光照強度、CO2濃度、溫度

31.(20分)【解析】:(1)該6個品系玉米的基因型分別為:①:AABBCCDDEE  ②:aaBBCCDDEE  ③:AAbbccDDEE  ④:AABBCCddEE  ⑤:AABBCCDDee  ⑥:aabbccddee

基因分離定律適用于一對等位基因控制的相對性狀的遺傳,基因自由組合定律適用于2對(及以上)的同源染色體上的2對(及以上)等位基因控制的性狀遺傳。具有兩對相對性狀的純合親本雜交,F(xiàn)1自交。若F2中出現(xiàn)性狀分離比為:雙顯∶單顯1∶單顯2∶雙隱=9∶3∶3∶1,則控制這兩對相對性狀的基因位于2對同源染色體上,反之則位于同一染色體上

讓F1側(cè)交,若F2中出現(xiàn)性狀分離比為:雙顯∶單顯1∶單顯2∶雙隱=1∶1∶1∶1,則控制這兩對相對性狀的基因位于2對同源染色體上,反之則位于同一染色體上

【答案】(1)②與①(③或、④、⑤) (1分)  不行  (1分)  品系①和⑤只有一對相對性狀   (2分)不行 (1分)  控制花色和種皮顏色的基因位于同一對同源染色體(Ⅰ)上,而控制子葉味道的基因位置未知(2分)

(2)D(1分)

①若綠色非甜子葉∶綠色甜子葉∶黃色非甜子葉∶黃色甜子葉=9∶3∶3∶1,則控制子葉顏色和味道的基因不是位于同一染色體上。(3分)

②若綠色非甜子葉∶綠色甜子葉∶黃色非甜子葉∶黃色甜子葉≠9∶3∶3∶1(答綠色甜子葉:綠色非甜子葉:黃色非甜子葉=1:2:1也可),則控制子葉顏色和味道的基因位于同一染色體上。(3分)

(3)

①若綠色非甜子葉∶綠色甜子葉∶黃色非甜子葉∶黃色甜子葉=1∶1∶1∶1,則控制子葉顏色和味道的基因不是位于同一染色體上。(3分)

②若綠色非甜子葉∶綠色甜子葉∶黃色非甜子葉∶黃色甜子葉≠1∶1∶1∶1(答綠色甜子葉:黃色非甜子葉=1:1也可),則控制子葉顏色和味道的基因位于同一染色體上。(3分)

 

 

 


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