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(14分)近年来我国的航天事业取得了巨大的成就，在航天发射时，肼(N 2 H 4 )及其衍生物常用作火箭推进剂。 ⑴液态肼作火箭燃料时，与液态N 2 O 4 混合发生氧化还原反应，已知每1 g肼充分反应后生成气态水放出热量为a KJ，试写出该反应的热化学方程式 。 ⑵在实验室中，用N 2 H 4 ·H 2 O与NaOH颗粒一起蒸馏，收集114～116 ℃的馏分即为无水肼。 ①在蒸馏过程中不需要的仪器是 (填序号字母)。 A．酒精灯 B．长直玻璃导管 C．锥形瓶 D．冷凝管 E．牛角管(接液管)   F．蒸馏烧瓶            G．酸式滴定管 ②除上述必需的仪器外，还缺少的玻璃仪器是 。 ⑶肼能使锅炉内壁的铁锈(主要成分Fe 2 O 3 )变成磁性氧化铁(Fe 3 O 4 )层，可减缓锅炉锈蚀。若反应过程中肼转化为氮气，则每生成1 mol Fe 3 O 4 ，需要消耗肼的质量为 g。 ⑷磁性氧化铁(Fe 3 O 4 )的组成可写成FeO·Fe 2 O 3 。某化学实验小组通过实验来探究一黑色粉末是否由Fe 3 O 4 、CuO组成(不含有其它黑色物质)。探究过程如下： 提出假设：假设1. 黑色粉末是CuO；假设2. 黑色粉末是Fe 3 O 4 ； 假设3. 。 设计探究实验： 取少量粉末放入足量稀硫酸中，在所得溶液中滴加KSCN试剂。 ①若假设1成立，则实验现象是 。 ②若所得溶液显血红色，则假设 成立。 ③为进一步探究，继续向所得溶液加入足量，若产生 的现象，则假设3成立。 有另一小组同学提出，若混合物中CuO含量较少，可能加入后实验现象不明显。 查阅资料：Cu 2 ＋ 与足量氨水反应生成深蓝色溶液，Cu 2 ＋ ＋4NH 3 ·H 2 O＝Cu(NH 3 ) 4 2 ＋ ＋4H 2 O。 ④为探究是假设2还是假设3成立，另取少量粉末加稀硫酸充分溶解后，再加入足量氨水，若假设2成立，则产生 现象；若产生 现象，则假设3成立。
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【单选题】认为只要企业产品质量好,价格公道,便会顾客盈门,而不必讲究销售方式。这种市场观念是 ( )
A.
生产观念
B.
产品观念
C.
推销观念
D.
市场营销观念
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【单选题】what makes the woman afraid of getting old?
A.
having little to look forward to
B.
facing the day to retire from work
C.
lack someone to depend on
D.
physical inability and loneliness
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【简答题】已知立体的主视图和俯视图,有三种不同的左视图,判断哪个是正确的?
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【单选题】What makes the woman upset?
A.
She hurts her arm very badly.
B.
She is worried about the concert.
C.
She fails to get a ticket for the concert.
D.
She makes no progress in violin-playing.
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【单选题】认为只要企业产品质量好、价格公道、便会顾客盈门,而不必讲究销售方式。这种观念是
A.
生产观念
B.
产品观念
C.
推销观念
D.
市场营销观念
查看完整题目与答案
【单选题】Q3 What makes the woman afraid of getting old?
A.
Having little to look forward to
B.
Facing the day to retire from work
C.
Physical inability and loneliness
D.
Lack of someone to depend on
查看完整题目与答案
【简答题】听下面一段材料，回答第1-3题。 1. What makes the woman worried? A. That she is too fat. B. That she has no nice clothes. C. That she will lose her job. 2. How is the woman? A. Very poor. B. Very busy. C. Very proud...
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【单选题】What makes the woman unhappy about?
A.
That she gets a chance to speak out.
B.
People like the convenience of cell phones.
C.
The way people use their cell phones in public places.
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【简答题】是一种 运用固定的格子设计版面空间布局的 平面设计方法与风格。
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【单选题】What makes the woman want to call Elizabeth?
A.
She owes her a great favor.
B.
She is sure that Elizabeth would help them.
C.
Elizabeth has always been so helpful.
D.
It’s still early.
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相关题目：
【单选题】认为只要企业产品质量好,价格公道,便会顾客盈门,而不必讲究销售方式。这种市场观念是 ( )
A.
生产观念
B.
产品观念
C.
推销观念
D.
市场营销观念
查看完整题目与答案
【单选题】what makes the woman afraid of getting old?
A.
having little to look forward to
B.
facing the day to retire from work
C.
lack someone to depend on
D.
physical inability and loneliness
查看完整题目与答案
【简答题】已知立体的主视图和俯视图,有三种不同的左视图,判断哪个是正确的?
查看完整题目与答案
【单选题】What makes the woman upset?
A.
She hurts her arm very badly.
B.
She is worried about the concert.
C.
She fails to get a ticket for the concert.
D.
She makes no progress in violin-playing.
查看完整题目与答案
【单选题】认为只要企业产品质量好、价格公道、便会顾客盈门,而不必讲究销售方式。这种观念是
A.
生产观念
B.
产品观念
C.
推销观念
D.
市场营销观念
查看完整题目与答案
【单选题】Q3 What makes the woman afraid of getting old?
A.
Having little to look forward to
B.
Facing the day to retire from work
C.
Physical inability and loneliness
D.
Lack of someone to depend on
查看完整题目与答案
【简答题】听下面一段材料，回答第1-3题。 1. What makes the woman worried? A. That she is too fat. B. That she has no nice clothes. C. That she will lose her job. 2. How is the woman? A. Very poor. B. Very busy. C. Very proud...
查看完整题目与答案
【单选题】What makes the woman unhappy about?
A.
That she gets a chance to speak out.
B.
People like the convenience of cell phones.
C.
The way people use their cell phones in public places.
查看完整题目与答案
【简答题】是一种 运用固定的格子设计版面空间布局的 平面设计方法与风格。
查看完整题目与答案
【单选题】What makes the woman want to call Elizabeth?
A.
She owes her a great favor.
B.
She is sure that Elizabeth would help them.
C.
Elizabeth has always been so helpful.
D.
It’s still early.
查看完整题目与答案
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