与罗红霉素在化学结构相似的药物是（） A.青霉素 B.土霉素 C.

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问题单项选择题 A1/A2型题

与罗红霉素在化学结构相似的药物是（）

A.青霉素

B.土霉素

C.红霉素

D.克拉维酸

E.四环素

答案

参考答案：C

解析：抗生素按化学结构分为：β-内酰胺类，代表药物有青霉素类和头孢菌素类；四环素类，代表药物有四环素和多西环素；大环内酯类，代表药物有红霉素和罗红霉素；氨基苷类，代表药物有链霉素和卡那霉素。

填空题

综合填空。

Are you able to send a letter with pictures and sounds to someone anywhere in the world without putting

a stamp on it? W______(1) e-mail you can just do that. Using a c______(2) you can send e-mail quickly and

easily. The post is much s______(3) than e-mail. E-mail can send i______(4) message to the other side of the

world in seconds.

E-mail is easy to use and it s______(5) time and money. The differences in time in different parts of the

world, do not matter w_______(6) sending e-mail. It is twenty-four-hour service that you can send e-mail at

any time of the day or n_______(7). No one has to be t_______(8) to receive e-mail. It d_______(9) matter

if your friends are in bed when you send e-mail to them, or you are seeing a f_______(10) at the cinema when

they send e-mail back.

填空题

已知电子工业上常用FeCl₃溶液来溶解电路板中的铜。某一反应体系有反应物和生成物共三种物质：FeCl₃、FeCl₂、Fe。完成下列问题：

（1）该反应中的还原产物的化学式是，氧化产物的化学式是。

（2）该反应中，发生还原反应的过程是（填化学式） → 。

（3）该反应的离子方程式为：。

（4）标出该反应电子转移的方向和数目

（5）如反应转移了0.3mol电子，则（填“溶解”或“生成”）的铁的质量为。