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5.魏主欲變北俗，引見群臣。……帝曰：“今欲斷諸北語，一從正音�！辈牧纤�反映的是北魏孝文帝的哪一項改革措施

A.改穿漢服　　 　　 B.采用漢姓　　 C.使用漢語　　　 D.與漢人通婚

4.秦國太守李冰為消除水患、灌溉農(nóng)田、改善民生而修建的水利工程是

A.都江堰　　 　　　 B.鄭國渠　　 　　 C.靈渠　　 　　　 D.大運河

3.漢代漢武帝為了鞏固大一統(tǒng)，在思想上采取的措施是

A.鼓勵推薦人才　 　　　　　　　　 B.頒布“推恩令”

C.“罷黜百家，獨尊儒術(shù)”　　　 　　 D.實行鹽鐵專營

2.中國歷史上第一個統(tǒng)一的多民族的封建國家是

A.夏　　 　　　　　 B.商　　 　　　　 C.周　　 　　　　 D.秦

1.一個歐洲旅游團隊要參觀我國到目前為止發(fā)現(xiàn)的最早的原始人類遺址，應該去

A.北京西南周口店　　　　　　　　　 B.浙江余姚河姆渡鎮(zhèn)

C.陜西西安半坡村　　　　　　　　　 D.云南元謀縣

首先要通讀全題，弄清實驗目的，實驗原理，然后運用所學知識大膽遷移，同時針對題干中信息準確細心答題，注重每個細節(jié)，特別提醒

(1)注意填寫容量瓶時，需帶容積規(guī)格

(2)化學用語的規(guī)范：如將溶液“褪色”寫成“退色”、注意“褪色”與“變色”的差別、“坩堝”寫成“坩鍋”、“溶”與“熔”的差別、分液漏斗的“開關(guān)”應為“活塞”、氣 體“跑掉”應為“逸出”等

(3)答題的規(guī)范性：如基本操作表達不完整(檢查氣密性、沉淀的洗滌、檢驗沉淀是否完全、焰色反應等)；答題空泛、復雜而不切合題示信息；答題未找到根本原因，因果關(guān)系不明了等

(4)按要求填寫“數(shù)字”或是“字母”，“偏高”或是“偏多”等

[例2-1]：凱氏定氮法測定奶粉中蛋白質(zhì)含量的步驟如下：

① 樣品處理：準確稱取奶粉試樣1.000 g置于燒瓶中，加入足量不含氮元素的試劑A，一定條件下充分反應，產(chǎn)物用水溶解并冷卻后全部轉(zhuǎn)移至100 mL容量瓶中定容。

② 堿化蒸餾：量取容量瓶中溶液10.00 mL轉(zhuǎn)移至右圖所示的反應管中，再加入足量NaOH溶液，塞好進樣口橡皮塞。通入高溫水蒸氣。用吸收劑吸收產(chǎn)生的氣體。

③ 滴定：向吸收氣體后的溶液中滴加2滴指示劑，用0.01 mol/LHCl標準溶液滴定至終點。

已知：吸收劑中發(fā)生的反應為：NH₃+4H₃BO₃＝NH₄HB₄O₇+5H₂O；

滴定時發(fā)生的反應為：NH₄HB₄O₇+HCl+5H₂O＝NH₄Cl+4H₃BO₃。

根據(jù)以上知識回答下列問題：

⑴　　 　樣品處理的目的是　　 ；通入高溫水蒸汽的作用除加熱外，還有　 　　。

⑵ 冷凝管的作用是冷凝、導氣、　 　　。

⑶ 若蛋白質(zhì)中氮元素的平均含量為16.0　%，滴定終點時消耗鹽酸標準液15.50 mL，則該奶粉中蛋白質(zhì)的含量為　 ▲　 %。

⑷ 凱氏定氮法測定奶粉中蛋白質(zhì)含量靈敏度高，操作簡單，缺點是　 ▲　 。

�？键c:

1化學常識和社會熱點　 2.基本化學用語　 3.阿伏加德羅常數(shù) 　4.化學基本概念

5化學實驗基礎(chǔ)知識　 　6、化學反應與能量　 7、氧化還原反應的概念及計算

8、離子共存問題　　　 9、元素周期律和元素周期表　 10、離子方程式正誤判斷

11有機基礎(chǔ)知識 12.電化學基礎(chǔ) 13.離子濃度及大小比較14.化學反應速率 化學平衡

解選擇題時的重點^____審題

(1)注意選擇題(特別是多選題)要求：正確的還是錯誤的(或不正確的)

(2)N_A相關(guān)考題需觀察全面、細致：與體積相關(guān)的是否為標準狀態(tài)、氣體；

(3)離子方程式的正誤判斷觀察需全面、細致：反應方程式是否存在或合理；改寫是否正確(注意區(qū)別膠體與沉淀)；電荷、原子是否守恒；隱含的反應是否遺漏(生成物與反應物不共存、隱含的氧化性物質(zhì)等)；方程式與所給的“量”的條件是否切合“過量”，“適量”，“足量”，“少量”。等

(4)在審題時注意關(guān)鍵文字信息，比如離子共存題中“無色溶液”， “酸性溶液”， “堿性溶液”；“一定”，“可能”，“一定不能” 等。元素周期表知識中“短周期元素”還是“前20號元素”等等。

(5)判斷型選擇題(“下列說法正確的是”)，考慮必須周全，切不可受習慣意識支配。

(6)注意題干中“混合物”、“化合物”“單質(zhì)”等要求

1.　 The Olympic Games, _____ in 776 BC., didn’t include women players until 1912.

A. first played　　 　　　　　　　 B. to be first played

C. first playing　　　 　　　　　 D. to be first playing

2.　　　 –I must apologize for _____ ahead of time.　 –That's all right.

A. letting you not know　　 　　　B. not letting you know

C. letting you know not　　　　　 D. letting not you know

3.　　　 –You were brave enough to raise objections at the meeting.

–Well, now I regret _____ that.

A. to do　　　 　 B. to be doing　 C. to have done　　 D. having done

4.　　　 The salesman scolded the girl caught _____ and left her off.

A. to have stolen　　　　　　　　 B. to be stealing

C. to steal　　　　　　　　　　　　 D. stealing

5.　　　 The first textbooks _____ for teaching English as a foreign language came out in the 16th century.

A. having written　　　　　　　　 　 B. to be written

C. being written　　　　　　　　　　 D. written

6.　　　 The visiting minister expressed his satisfaction with the talks, _____ that he had enjoyed his stay here.

A. having added　 B. to add　　　 C. adding　　　　 D. added

7.　　　 The patient was warned _____ oily food after the operation.

A. to eat not　　　　 B. eating not　 C. not to eat　 D. not eating

8.　　　 –Can you spare me some time?　 –I'm afraid not. I have lots of letters _____.

A. doing with　　 B. to do for　　　 C. to deal　　 D. to deal with

9.　　　 I can't understand _____ at that poor child.

A. you to laugh　 B. you laughing C. you laugh　　 D. why laugh

10.　　 We must set about _____ our lesson for the mid-term examination.

A. reviewing　　 B. reviewed　　　 C. to review　　 D. to reviewing

11.　　 I found John _____ the desk, _____ his homework carefully.

A. seated at; to do　　　　　　　 B. sitting at; doing

C. sat at; does　　　　　　　　　 D. taking his seat at; to do

12.　　 _____, he suddenly found the shop he was looking for.

A. When he turns round　　　　　　 B. To turn the left

C. Turned backward　　　　　　　 D. Turning to the left

13.　　 Is this the watch you wish _____?

A. to have repaired　　　　　　　 B. to repair it

C. to have it repaired　　　 　　　 D. will be repaired

14.　　 This is the problem _____ at the next meeting.

A. to discussing　　 　　　　　　　 B. to be discussed

C. discussed　　 　 D. being discussed

15.　　 _____ many times, but he still couldn't understand it.

A. Having been told　　　　　　　 B. Though he had been told

C. He was told　　　　　　　　　 D. Having told

16.　　 It is considered no good _____ in the hotel.

A. recite　 B. to be recited　　 C. recited　　　　 D. reciting

17.　　 With lost of trees _____, the house is not easily found.

A. to surround　　 　　　　　　　　 B. surrounding

C. having surrounded　　 　　　　 D. surrounded

18.　　 –Did you get your pay?

　　 –Yes, I remember _____. But I forget the exact amount.

A. paying　　　 B. to be paid　　 C. being paid　　 D. having paid

19.　　 Many teachers were praised at the meeting, Mr. Zhou _____.

A. including　 B. being included　 C. to include　 D. included

20.　　 I _____ the truth of your remarks, although they go against my interests.

A. cannot but admit　　　　　　　 B. cannot but to admit

C. cannot but admitting　　　　　 D. cannot help but admitting

21.　　 Professor Smith is said _____ another important discovery in chemistry.

A. having made　 B. making　　　 C. to have made　　 D. to make

22.　　 _____ by the appearance, he has just been frightened at the terrible news.

A. Judged　　 　 B. To be judged　 C. Judging　　　 D. Judge

23.They used what they had _____ for their daughter.

A. to buy a new dress　　　　　　 B. buying a new clothes

C. bought a new suit　　　　　　　 D. buy a new clothing

24.I don't mind _____ the decision as long as it is not too late.

A. you to delay making　　　　　　B. your delaying making

C. your delaying to make　　　　　D. you delay to make

25.The sale usually takes place outside the house, with the audience _____ on benches, chairs or boxes.

A. having seated　　 　　　　　　 B. seating

C. seated　　　 　　　　　　　　　 D. having been seated

01-05：ABDDD　　 06-10：CCDBA　 11-15：BDABC　 16-20：DDCDA

21-25：CCABC

3. NH₄⁺的檢驗方法：加　　 液，加熱，放出可使?jié)駶櫟募t色石蕊試紙變　　 的氣體。

原理為：　　　　　　　　　　　　　

2.化學性質(zhì)

①受熱易分解：

NH₄Cl 　　　　　　　　　　　　NH₄HCO₃

②與堿的反應：(用于制NH₃和檢驗NH₄⁺)

(NH₄)₂SO₄+NaOH 　　　　　　NH₄Cl + Ca(OH)₂