下列食物链符合生物学原理的是（） A．阳光→草→鼠→鹰 B．植物→蚜虫→瓢虫→细

同一种组分液体的蒸汽压随温度的升高而增大，随着温度的下降而减小。

阅读理解。

     American  eating  is  funny. People  in  America  eat  almost everything with a  fork. And it seems that

holding a knife in one's right hand longer than a few seconds is thought to be against good table manners.

     The system is that if it is necessary to use a knife, people take the fork in their left hands, and cut off a

piece of meat or others. Then  they  put  the knife down, transfer the fork to  their  right  hands, and then

transfer the food to their mouths with  the fork.  This is clearly funny, but it is considered  good  manners.

     There are several results of this system. First,if it is not necessary to use a knife, Americans don't  use

one, because this greatly complicates（使复杂化）things. Therefore, sometimes they will try to cut things like potatoes and even bacon with a fork. Second, since only one implement（器具）is being used, food has to be chased around the plate with the fork. Third, tables are usually laid with one knife and two forks. The outside fork is for the salad. There is no  need for foreign  visitors to follow the  American system and

try to eat the salad with only a fork, but if you do use your knife, remember to save it for the meat.

1. The word "transfer" most probably means “________”.

A. move something from one place to another    

B. make up and down

C．take away

2. From this passage we can know that _______.

A. Americans never use knives with their right hands

B. Americans eat everything with a knife

C. Americans use a fork to put food into their mouths

3. According to the passage, Americans eat potatoes with a fork probably because ______.   

A. they are too busy to use a knife    

B. there is no knife

C. they think it is complicated to use a knife

4. Which of the following about American eating is NOT true?

A. Holding a knife in one's right hand longer is not good table manners.

B. Americans will not use a knife if they don't need.

C. Foreign visitors are not allowed to use knives.

5. The best title for this passage is _______.

A. Right Hand or Left Hand    

B. Knife or Fork

C. Eating Customs in America

“低碳循环”引起各国的高度重视，而如何降低大气中CO₂的含量及有效地开发利用CO₂，引起了全世界的普遍重视。所以“低碳经济”正成为科学家研究的主要课题

(1)用电弧法合成的储氢纳米碳管常伴有大量的碳纳米颗粒（杂质），这种颗粒可用如下氧化法提纯，请完成该反应的化学方程式：

(2)将不同量的CO（g）和H₂O（g）分别通入到体积为2L的恒容密闭容器中，进行反应

CO（g）＋H₂O（g）CO₂（g）＋H₂（g），得到如下三组数据

该反应为________（填“吸”或“放”）热反应，实验2条件下平衡常数K=___________。

(3)已知在常温常压下：

① 2CH₃OH(l) ＋ 3O₂(g) ＝ 2CO₂(g) ＋ 4H₂O(g) ΔH ＝－1275.6 kJ/mol

② 2CO (g)+ O₂(g) ＝ 2CO₂(g) ΔH ＝－566.0 kJ/mol

③ H₂O(g) ＝ H₂O(l) ΔH ＝－44.0 kJ/mol

写出甲醇不完全燃烧生成一氧化碳和液态水的热化学方程式：__________________________。

(4)某实验小组依据甲醇燃烧的反应原理，设计如图所示的电池装置。工作一段时间后，测得溶液的pH减小，该电池总反应的化学方程式为_____________________。

(5)CO₂在自然界循环时可与CaCO₃反应，CaCO₃是一种难溶物质，其Ksp=2.8×10^-9。CaCl₂溶液与Na₂CO₃

溶液混合可形成CaCO₃沉淀，现将等体积的CaCl₂溶液与Na₂CO₃溶液混合，若Na₂CO₃溶液的浓度为

2×10^-4mol/L ，则生成沉淀所需CaCl₂溶液的最小浓度为______________。

下列关于高锰酸钾制氧气的说法中正确的是（　　）

A．收集氧气可用排水法

B．加热时，试管口应略向上倾斜，防止药品洒落

C．连接仪器时应从左到右，从上到下

D．收集满氧气的集气瓶应倒放在试验台上

机床各电动机的振动，是（）振源。

A、机内

B、机外

C、机内机外都有