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问题 选择题

温室大棚能反季节种植蔬菜，主要是改变了下列哪个要素（   ）

A 热量  B 水分  C 土壤  D 光照

答案

答案：A

题目分析：温室大棚的保温效应能改善热量条件。

点评：本题难度低，学生只要掌握温室大棚生产的基本原理即可判断。

单项选择题

George Bernard Shaw wrote: "That any sane nation, having observed that you could provide for the supply of bread by giving bakers a pecuniary interest in baking for you, should go on to give a surgeon a pecuniary interest in cutting off your leg is enough to make one despair of political humanity. Shaw’s statement would best serve as an illustration in an argument criticizing which of the following

A．Dentists who perform unnecessary dental work in order to earn a profit.

B．Doctors who increase their profits by specializing only in diseases that affect a large percentage of the population.

C．Grocers who raise the price of food in order to increase their profit margins.

D．Oil companies that decrease the price of their oil in order to increase their market share.

E．(E) Bakers and surgeons who earn a profit by supplying other peoples’ basic needs.
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问答题

化学是一门以实验为基础的自然科学，化学实验在化学学习中具有极其重要的作用．

（1）如图实验没有错误的是______．

（2）如图为常见仪器的部分结构（有的仪器被放大）、

A图中液面所示溶液的体积为______mL，用上述四种仪器中的某种测量一液体的体积，平视时读数为NmL，仰视时读数为MmL，若M＞N，则所使用的仪器是______（填字母标号）．

（3）化学研究小组，通过网上查找资料发现，Cl2的制取有下列不同方案：

a、方案：加热条件下二氧化锰与浓盐酸反应制得C2

b、方案：浓盐酸与氯酸钾固体反应制得Cl2

c、方案：电解饱和食盐水法制得Cl2

现实验室有供选择的如下几种仪器来制取Cl2

①用上述仪器不能实现的方案为______．不考虑固定装置的仪器，可行但缺仪器的方案是______，所缺的仪器是______．

若按b方案制Cl2时发生化学方程为______，

②若要设计联合实验探究氯气的漂白原理，从制备装置中产生氯气后应连接的装置中所使用的试剂或用品依次是______．
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