根据图中所示.写出图中每个地点相对的位置.充分运用学过的表示方位的一些介词或介词短语.(要求:语句流畅.标点正确.充分利用写作材料.60字以上) 出题人:雷玉香 冯文静 审题人:曾朝晖 查看更多

 

题目列表(包括答案和解析)

阿司匹林(乙酰水杨酸)已应用百年,成为医药史上三大经典药物之一,至今它仍是世界上应用最广泛的解热、镇痛和抗炎药,也是作为比较和评价其他药物的标准制剂。乙酰水杨酸受热易分解,分解温度为128~135℃。某学习小组在实验室以水杨酸(邻羟基苯甲酸)与醋酸酐[(CH3CO)2O]为主要原料合成该物质,设计的合成路线为:
一、制备K
s*5u
二、提纯
方案1
方案2
主要试剂和产品的物理常数
名    称
相对分子质量
熔点或沸点(0C)



水杨酸
138
158(熔点)
微溶
易溶
易溶
醋酸酐
102
139.4(沸点)
反应
可溶
易溶
乙酰水杨酸
180
135(熔点)
微溶
可溶
微溶
请根据以上信息回答下列问题:                   
(1)①合成阿斯匹林时,还会生成一些副产品,其中有一种是高分子,为了分离此物质,方案1中加入A物质为      溶液。
②本方案抽滤后进行洗涤,其具体操作是       
(2)方案2为改进的提纯方法,称为重结晶提纯法。
①该方案中步骤1除了选用乙酸乙酯外,还可选择下列哪些
试剂      
A. 乙醇      B. 蒸馏水      C. 乙醚   
②步骤2回流的装置如图所示,写出仪器a的名称      ,使用温度计的目的是      ,冷凝水的流向为       

③方案2所得产品的有机杂质要比方案1少的原因是      
(3)该学习小组在实验中原料用量:2.0g水杨酸、5.0ml醋酸酐(ρ=1.08g·cm-3),
最终称量产品m="2.2g" ,则乙酰水杨酸的产率为       。

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根据句意和汉语意思写出句中所缺单词(共10小题;每小题1分,满分10分)

1.He___________ (总是)reads books about football.

2.Tom gets lots of ___________(礼物) from his friends on his birthday.

3.Don’t do that     __   (再).

4.This is one of the biggest_____________(餐馆)in Beijing.

5.I often go to my ______________(祖父母)home on Sundays.

6.Thank you for ____________ (组织)this English party.

7.I can look for lots of ____________ (信息)on the Internet.

8.What’s the ________ (价格)of the shirt?

9.It’_______________(传统的)to eat turkey on Thanksgiving Day.

10.Andy likes making__________(模型)planes very much.

 

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你能根据汉语提示或句意,写出句中所缺单词吗? (5分)

1.How many            (图书馆) are there in your school?

2.I feel cold. Please          the window.         

3.           (动物) are our friends. We should love them.

4.We should be            (礼貌) to the old.

5.We call uncle’s father             .

 

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根据句意及提示,写出句中所缺的单词。
1.Do you play an _______(积极的) part in the class activities.
2. —Your white blouse _____________(与……相配) your black trousers very well.
—Thank you.
3. My uncle is an    (精力充沛的) businessman. He always works till midnight.
4. He lives a simple life. He likes _____________(储蓄) money.
5. Dr Bethune was busy performing an __________(手术) on the dying man.

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根据句意及提示,写出句中所缺的单词。
1.Do you play an _______(积极的) part in the class activities.
2. —Your white blouse _____________(与……相配) your black trousers very well.
—Thank you.
3. My uncle is an    (精力充沛的) businessman. He always works till midnight.
4. He lives a simple life. He likes _____________(储蓄) money.
5. Dr Bethune was busy performing an __________(手术) on the dying man.

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