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根据句意和首字母填空(5分)
1.Let’s go to the zoo on weekends. There are many new a _________ there.
2.He doesn’t want to do any homework and he is l _________.
3.The e_________ has a long nose and two big ears.
4.This yellow skirt looks very b_________. I want to buy one for my mother.
5.I have two uncles. One is a runner, and the o_________ is an actor.
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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 | 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>>
实验1：将切除的胚芽鞘尖端放置于琼脂块上(图1)，移去尖端后，将琼脂切成体积相等的若干个方块，将方块放在除去尖端的胚芽鞘上，实验进行一定时间后，每个胚芽鞘弯曲的角度以图2的方法测量，并计算平均值。每次放在等面积、等体积琼脂块上的胚芽鞘尖端数量不同，这样重复上述过程。
实验2：用含有不同浓度IAA的琼脂块代替胚芽鞘尖端进一步实验。上述两个实验的结果如图3和图4所示。
（1）绘图表示，如何将琼脂块放置于胚芽鞘上，才能得到图3的结果?
（2）解释实验2的结果：IAA从0μmol/L～1.3μmol/L过程中 ；1.3μmol/L～1.8μmol/L过程中 。
（3）①比较实验1和实验2的结果有什么不同? 。
②为什么会出现这种不同？ 。
（4）从本实验可知促进胚芽鞘生长的最适生长素浓度约为_______
图4中曲线上b点对应生长素浓度时胚芽鞘弯曲角度为17度，把琼脂块去掉后，胚芽鞘最终会如何生长？________ 查看习题详情和答案>>
根据首字母提示和句意完成单词
1.How about l to the radio?
2.Now,let me show you how to l English.
3.Why don’t you write d your mistakes?
4.I’m going to meet my p friend this term.
5.Can you give me some a ?My English is so poor.
6.I enjoy w English films and l to real English songs.
7.The students should speak English all the t in English class.
8.Many students ask for advice about i their English.
9.Did you enjoy y at the party?
10.Write the words on p of paper and place them in your bedroom.
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补全对话
A．It's polite to leave at least half an hour after the meal．
B．You are supposed to leave at once．
C．What are you nervous about?
D．you are supposed to stay for the whole evening．
E．It's impolite to arrive late．
F．You stay for an hour．
(Lin Tao要去英国做交换生，她向笔友Alice了解英国礼仪。L=Lin Tao；A=Alice)
L：Hi，Alice.I'm going to England as an exchange student．
A：Great!
L：But I'm a little nervous．
A：1
L：Well．I don't know much about the customs and manners in England．Could you help me?
A：Hmm，Let me see．They think it's important to be on time when you're invited to lunch，dinner or supper．2 As it is usually planned to have the meal at the exact hour given in the invitation．
L：Then how long may I stay there?
A：3 Otherwise it seems you have come only for the meal．An evening dinner invitation usually meals that 4 The hostess often plans some after-dinner entertainments.
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