5.将硫粉/碳粉/铜粉与浓硫酸/硝酸共热
S+2H2SO4(浓)△3SO2↑+2H2O
C+2H2SO4(浓)△ CO2↑+2SO2↑+2H2O
Cu+2H2SO4(浓)△ CuSO4+SO2↑+2H2O
S+6HNO3(浓)△ H2SO4+6NO2↑+2H2O
C+4HNO3(浓)△ CO2↑+4NO2↑+2H2O
Cu+4HNO3(浓)==Cu(NO3)2+2NO2↑+2H2O
(浓H2SO4、浓HNO3与非金属反应 只作氧化剂; 与金属反应既作氧化剂又作酸。)
4. 铜粉/铁粉与硫粉共热
2Cu+SCu2S(黑色)(S的氧化性不强,只能将变价金属氧化成低价态)
Fe+SFeS(黑色)
3.实验室制氢氟酸 / 氢氟酸腐蚀玻璃
NaF+H2SO4==Na2SO4+2HF↑ (反应须在铅皿或塑料制品中进行)
4HF+SiO2==SiF4↑+2H2O
2. 漂白粉在空气中变质 / 在工业上应用
Ca(ClO)2+CO2+H2O==CaCO3↓+2HClO (在空气中变质)
Ca(ClO)2+2HCl==CaCl2+2HClO (工业上应用)
1.铁/铜在氯气中燃烧(方程式及现象)
2Fe+3Cl22FeCl3(产生棕黄色的烟,加水振荡,溶液呈黄色)
Cu+Cl2CuCl2(产生棕色的烟,加水振荡,溶液呈蓝绿色)
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
书面表达评分参考:
1.第一档: (15-14分) (很好)
完全完成试题规定的任务。运用了多样的句式和丰富的词汇,语法或用词方面有个别错误,但为尽可能表达丰富的内容所致;体现了较强的语言运用能力。全文结构紧凑,逻辑清楚、合理。
2.第二档: (13-11分) (好)
完成试题规定的任务。运用的句式和词汇能满足任务要求,语法和用词基本准确,少许错误主要为尽可能表达丰富的内容所致。使用了简单的语句间连接成分,内容连贯,逻辑清楚、合理。
3.第三档: (10-9分) (及格)
基本完成试题规定的任务。运用的句式和词汇基本满足任务要求,语法和用词方面有一些错误,但不影响理解。内容基本连贯,逻辑清楚、合理。
4.第四档: (8-5分) (较差)
未恰当完成试题规定的任务。所用句式和词汇有限,语法或用词方面的错误影响了对所写内容的理解。信息未能清楚地传达给读者。
5.第五档: (4-0分) (差)
未完成试题规定的任务。句式单调,词汇贫乏,语法或用词方面错误较多,严重影响了对所写内容的理解。信息未能传达给读者。
6.书写或标点符号不规范在4处以上(含4处),或字迹潦草,在得分中再扣除1分(第四、五档文不扣此项分数)。重复错误只扣一次分数。
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
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