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5．將硫粉/碳粉/銅粉與濃硫酸/硝酸共熱

S+2H₂SO₄(濃)△3SO₂↑+2H₂O　　

C+2H₂SO₄(濃)△ CO₂↑+2SO₂↑+2H₂O　

Cu+2H₂SO₄(濃)△ CuSO₄+SO₂↑+2H₂O　

S+6HNO₃(濃)△ H₂SO₄+6NO₂↑+2H₂O

C+4HNO₃(濃)△ CO₂↑+4NO₂↑+2H₂O

Cu+4HNO₃(濃)==Cu(NO₃)₂+2NO₂↑+2H₂O

(濃H₂SO₄、濃HNO₃與非金屬反應(yīng) 只作氧化劑； 與金屬反應(yīng)既作氧化劑又作酸。)

4. 銅粉/鐵粉與硫粉共熱

2Cu+SCu₂S(黑色)(S的氧化性不強(qiáng)，只能將變價(jià)金屬氧化成低價(jià)態(tài))

Fe+SFeS(黑色)

3．實(shí)驗(yàn)室制氫氟酸 / 氫氟酸腐蝕玻璃

NaF+H₂SO₄==Na₂SO₄+2HF↑　 (反應(yīng)須在鉛皿或塑料制品中進(jìn)行)

4HF+SiO₂==SiF₄↑+2H₂O

2. 漂白粉在空氣中變質(zhì) / 在工業(yè)上應(yīng)用

Ca(ClO)₂+CO₂+H₂O==CaCO₃↓+2HClO　 (在空氣中變質(zhì))

Ca(ClO)₂+2HCl==CaCl₂+2HClO　 (工業(yè)上應(yīng)用)

1．鐵/銅在氯氣中燃燒(方程式及現(xiàn)象)　　

2Fe+3Cl₂2FeCl₃(產(chǎn)生棕黃色的煙，加水振蕩，溶液呈黃色)

Cu+Cl₂CuCl₂(產(chǎn)生棕色的煙，加水振蕩，溶液呈藍(lán)綠色)

One possible version:

Dear teachers and students，

　　　 Our government is trying hard to promote scientific development. As a student, we have a responsibility to work hard and reach this goal.

　　　 However, not everybody has realized the importance of it. Take our school for example. Sometimes we can see that lights and computers are still on after class. Some students even forget to turn off the tap after using it and have water running all the time. Only one side of the paper is used, causing much waste.

　　　 Therefore, to avoid this kind of waste, we advocate that each person play their part. Firstly, make sure that all the lights and other electric facilities are turned off when we leave the rooms. Secondly, try to form the habit of turning off the tap immediately after using it. What’s more, both sides of the papers should be used and reused if possible.

　　　 T sum up, if we add up all these small changes made by everyone, they won’t be such small changes. They could be the changes that save our future.

Students’ Union

書面表達(dá)評(píng)分參考：

1．第一檔: (15-14分) (很好)　　　

完全完成試題規(guī)定的任務(wù)。運(yùn)用了多樣的句式和豐富的詞匯，語法或用詞方面有個(gè)別錯(cuò)誤，但為盡可能表達(dá)豐富的內(nèi)容所致；體現(xiàn)了較強(qiáng)的語言運(yùn)用能力。全文結(jié)構(gòu)緊湊，邏輯清楚、合理。

2．第二檔: (13-11分) (好)

完成試題規(guī)定的任務(wù)。運(yùn)用的句式和詞匯能滿足任務(wù)要求，語法和用詞基本準(zhǔn)確，少許錯(cuò)誤主要為盡可能表達(dá)豐富的內(nèi)容所致。使用了簡(jiǎn)單的語句間連接成分，內(nèi)容連貫，邏輯清楚、合理。

3．第三檔: (10-9分) (及格)

基本完成試題規(guī)定的任務(wù)。運(yùn)用的句式和詞匯基本滿足任務(wù)要求，語法和用詞方面有一些錯(cuò)誤，但不影響理解。內(nèi)容基本連貫，邏輯清楚、合理。

4．第四檔: (8-5分) (較差)

未恰當(dāng)完成試題規(guī)定的任務(wù)。所用句式和詞匯有限，語法或用詞方面的錯(cuò)誤影響了對(duì)所寫內(nèi)容的理解。信息未能清楚地傳達(dá)給讀者。

5．第五檔: (4-0分) (差)

未完成試題規(guī)定的任務(wù)。句式單調(diào)，詞匯貧乏，語法或用詞方面錯(cuò)誤較多，嚴(yán)重影響了對(duì)所寫內(nèi)容的理解。信息未能傳達(dá)給讀者。

6．書寫或標(biāo)點(diǎn)符號(hào)不規(guī)范在4處以上(含4處)，或字跡潦草，在得分中再扣除1分(第四、五檔文不扣此項(xiàng)分?jǐn)?shù))。重復(fù)錯(cuò)誤只扣一次分?jǐn)?shù)。

1. exposed　 2. unfortunately/unluckily　 3. hearing　　 4. increases　　 5. Soundproof

6. However　 7. caused/created　　　 8. enforce　　 9. joining　　　 10. yourself

4. beyond our control　　　　 5. wipe out AH1N1 flu/ stop AH1N1 flu in its tracks

1. has a gift for　　　　　　　　　 2. in vain　　　 3. break away from

1. sharpen　　 2. deadline　　 3. threatening　　 4. annually/yearly　　 5. unconscious