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一、制备K
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 | 醇 | 醚 |
| 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 |
(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 ▲ 。 查看习题详情和答案>>
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.
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. 查看习题详情和答案>>