问题 多项选择题

下列项目中,属于存货成本的是()。

A.取得成本

B.机会成本

C.储存成本

D.缺货成本

E.管理成本

答案

参考答案:A, C, D

实验题

下图是实验室中用于制取、干燥和收集气体的装置图。实验课上同学们用过氧化氢溶液与二氧化锰混合制取并收集氧气,试回答:

(1)写出A图中带标号仪器的名称:①_______,②________。

(2)用该方法制取氧气的化学方程式是_________________。

(3)该方法制取氧气的发生装置应选择___________,若用C装置采用排水法收集氧气,进气口为____________。(填a或b)

(4)若用D装置干燥氧气,D中应盛放的试剂是__________。

(5)甲、乙、丙三名同学用所选装置合作探究过程中,胶塞突然弹飞,并有少量的液体溅到实验台和衣服上。就此异常现象三名同学探究如下:

【问 题】为什么胶塞会突然弹飞呢?

【查阅资料】①容器内瞬间产生气体过多,压强过大,可能导致胶塞弹飞。 ②化学反应速率与反应物的浓度、接触面积、温度、催化剂等因素有关。

【猜 想】甲同学:导气管堵塞或弯折造成的。 乙同学:过氧化氢溶液用量过多造成的。 丙同学:过氧化氢溶液的溶质质量分数过大造成的。

【分析验证】通过检查实验装置发现导气管没有堵塞、弯折的情况;与实验成功的小组同学交流,得知各小组所用过氧化氢溶液溶质的质量分数均相同。于是他们否定了________两名同学的猜想。请你设计实验,验证另一名同学的猜想是导致本次实验胶塞弹飞的主要原因。

【交流反思】

(1)老师建议他们可以通过改进发生装置的方法,避免胶塞弹飞。你对所选的发生装置有何改进设想?

____________________________(语言叙述或画图均可)

(2)实验结束后,有的同学发现衣服和手上出现有白色的斑点。由此推出过氧化氢溶液还具有的一条性质___________________________。

填空题

Good afternoon, everybody. I’m pleased to be here with you, graduates of 2007. I’m a (1) , and students often approach me with (2) . You see, we are living in a society of great changes. With the presence of (3) , the process of getting a job in today’s world has changed for (4) .
Well, how can you use new technologies to help you First, let’s look at how you (5) . The traditional method of hunting for a job in the past required first, doing research on jobs that were (6) , typically by looking in newspapers, periodicals and magazines, as well as TV ads, and (7) . Then you decided where and for what post you were going to apply, put your resume (8) in a stamped envelope, and waited anxiously for someone to (9) .
Well, today, maybe the job search and (10) are very much the same, but the tools used are much more advanced, and they (11) . In fact, technology has not so much changed the process as enhanced it. The benefit, both for (12) , is that this makes the search more open to people of (13) from all over the world. But as more people are involved, it becomes (14) for the applicant than it ever was before.
The (15) for the working world today is learning these new and (16) and combining them with the older methods people have been using for years. For example, (17) , you can research employment not just in your city, but also in your state, your country, and (18) . You can copy information from a web page and paste it into a Microsoft Word document that’s easy to (19) . In many ways, it’s easier now: Just type your job application, click, and (20) ; it gets there in an instant.