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某化学课外小组利用H 2 还原R 2 O 3 粉末测定R元素的相对原子质量，图是测量装置的示意图（加热装置和夹持装置略去），A中的试剂是稀盐酸，B中加入的是锌粒． 请回答下列问题： （1）连接好装置后的实验操作依次是______（填操作序号） ①检验氢气纯度  ②加热E  ③检验装置气密性  ④点燃G管逸出的气体  ⑤从A瓶逐滴滴加液体 （2）C中的试剂是______，其作用为______． （3）从G管逸出的气体需要点燃除去的原因是______． （4）在稀盐酸中加入稍许CuSO 4 溶液，发现B中产生气体的速度明显加快，你认为原因是______． （5）该化学课外小组从实验中测得了下列数据： ①空E管的质量a；②E管和R 2 O 3 的总质量b；③反应后E管和R粉的总质量c（冷却到温室称量）；④反应前F管及内盛物的总质量d；⑤反应后F管及内盛物的总质量e； 根据以上数据可以列出三个计算R的相对原子质量的不同计算式（除R外，其它涉及的元素的相对原子质量均为已知）： 计算式1：Ar（R）=______； 计算式2：Ar（R）=______； 计算式3：Ar（R）=______．
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【简答题】根据首字母或汉语提示完成单词。 1. He has received many g_____ on his birthday. 2. We visit my grandma every Sunday and she always cooks s_____dishes for us. 3. —Why don't you get a camera? —That's too e_____. 4. Tom...
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【单选题】听力原文：W: Henry, why don't we go out to lunch today and visit some friends? M: And miss today's football game? Washington and Los Angeles are playing and this will be one of the best games of the year Q...
A.
He is going to join in the game.
B.
He is going to Washington and Los Angeles.
C.
He wants to watch the football game.
D.
He doesn't care if he misses the game.
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【单选题】听力原文：W: Henry, why don't we go out to lunch today and visit some friends? M：And miss today's football game? Washington and Los Angeles are playing and this will be one of the best games of year. Q: Wh...
A.
He is going to join in the game.
B.
He is going to Washington and Los Angeles.
C.
He wants to watch the football game.
D.
He doesn't care if he misses the game.
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A.
正确
B.
错误
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1400
B.
2000
C.
3100
D.
2100
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【单选题】听力原文：M: I just heard about a really beautiful park in the east end of town. There are supposed to be a lot of roses in bloom. W: why don't we walk over there and see for ourselves? Q: What will the sp...
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Plant some rose bushes in the yard.
B.
Cut some fresh flowers.
C.
Visit the park.
D.
Talk to someone who has visited the park.
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【简答题】根据所给的汉语提示，转换下列句型。 1. Is there an interesting place to visit? Could you tell me? (合并为一句) Could you tell me _____ _____ an interesting place to visit? 2. Why don't we go to an art museum? (改为同义句) _____ ...
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【单选题】听力原文：M: So, what do you want to do tomorrow? W: Well, let's look at this city guide here. Uh, here's something interesting. Oh! Why don't we first visit the art museum in the morning. M: Okay. I like ...
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【简答题】银行要想实现持续的差异化,()是根本。
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【简答题】根据首字母或汉语提示完成单词。 1. He has received many g_____ on his birthday. 2. We visit my grandma every Sunday and she always cooks s_____dishes for us. 3. —Why don't you get a camera? —That's too e_____. 4. Tom...
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【简答题】(1)It will only be a ______ (短暂的) visit because we recently haven't much time. (2)The job is great ___________ (在...方面)advancement but the starting salary is rather low. (3)We had better pay that elec...
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【单选题】听力原文：W: Henry, why don't we go out to lunch today and visit some friends? M: And miss today's football game? Washington and Los Angeles are playing and this will be one of the best games of the year Q...
A.
He is going to join in the game.
B.
He is going to Washington and Los Angeles.
C.
He wants to watch the football game.
D.
He doesn't care if he misses the game.
查看完整题目与答案
【单选题】听力原文：W: Henry, why don't we go out to lunch today and visit some friends? M：And miss today's football game? Washington and Los Angeles are playing and this will be one of the best games of year. Q: Wh...
A.
He is going to join in the game.
B.
He is going to Washington and Los Angeles.
C.
He wants to watch the football game.
D.
He doesn't care if he misses the game.
查看完整题目与答案
【判断题】商品包装仅指对商品的包裹 , 捆扎物的总称。
A.
正确
B.
错误
查看完整题目与答案
【单选题】A.B两家公司同属甲公司的子公司。A公司于2008年3月1日以发行股票方式从B公司的股东手中取得B公司70%的股份。A公司发行2000万股普通股股票,该股票每股面值为1元;发行手续费总额为100万元。B公司在2008年3月1日所有者权益账面价值为3 000万元,A公司该项长期股权投资的入账价值为( )万元。
A.
1400
B.
2000
C.
3100
D.
2100
查看完整题目与答案
【单选题】听力原文：M: I just heard about a really beautiful park in the east end of town. There are supposed to be a lot of roses in bloom. W: why don't we walk over there and see for ourselves? Q: What will the sp...
A.
Plant some rose bushes in the yard.
B.
Cut some fresh flowers.
C.
Visit the park.
D.
Talk to someone who has visited the park.
查看完整题目与答案
【简答题】根据所给的汉语提示，转换下列句型。 1. Is there an interesting place to visit? Could you tell me? (合并为一句) Could you tell me _____ _____ an interesting place to visit? 2. Why don't we go to an art museum? (改为同义句) _____ ...
查看完整题目与答案
【单选题】听力原文：M: So, what do you want to do tomorrow? W: Well, let's look at this city guide here. Uh, here's something interesting. Oh! Why don't we first visit the art museum in the morning. M: Okay. I like ...
A.
Italian.
B.
Indonesian.
C.
Indian.
D.
French.
查看完整题目与答案
【简答题】银行要想实现持续的差异化,()是根本。
查看完整题目与答案
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