问题 问答题

请结合下列实验常用装置,回答有关问题.

(1)写出图中标有字母的仪器的名称:a______.

(2)实验室用高锰酸钾制取氧气,应选用的发生装置是______,在加入药品前,应首先检查装置的______,反应的化学方程式是______.

(3)若要制取二氧化碳,在B装置中装有石灰石,稀盐酸应从______中加入.其化学方程式为______.若要获得干燥的二氧化碳,除发生装置外,还应选用D装置,并在该装置中盛放______(填写试剂名称).如果用E装置收集该气体,则气体从______端进入(填“b”或“c”).

(4)实验室如用块状固体和液体无需加热制取气体,可将B装置改进为C装置(多孔隔板用来放块状固体),其优点是______.

答案

(1)直接写出仪器的名称为长颈漏斗;

(2)高锰酸钾是固体,再用高锰酸钾制取氧气时需要加热,所以应该选择Z装置来作为发生装置,在加入高锰酸钾之前要保证装置的气密性是良好的,所以必须先先检查装置的气密性,该反应的化学方程式为:2KMnO4

  △  
.
 
K2MnO4+MnO2+O2↑;

(3)长颈漏斗的作用就是方便向锥形瓶中加入稀盐酸的,二氧化碳的是酸性气体,所以应该选择浓硫酸来干燥,故在D装置中应该加入浓硫酸,由于二氧化碳的密度比空气的大所以在用E装置来收集二氧化碳时应该从b管进入,实验室中制取二氧化碳的化学方程式为:CaCO3+2HCl═CaCl2+H2O+CO2↑;

(4)在装置C中加入了多孔隔板,可以通过弹簧夹来控制反应,在需要的时候随时开始或终止实验.

故答案为:(1)长颈漏斗

(2)A;气密性;2KMnO4

 点燃 
.
 
K2MnO4+MnO2+O2↑;

(3)a(或长颈漏斗);CaCO3+2HCl═CaCl2+H2O+CO2↑;浓硫酸;b;

(4)随时控制反应的发生与停止.

阅读理解

阅读理解。

     Australia has lots of lovely animals. You can't find them anywhere else in the world. The most famous

ones are kangaroos and koalas.

     The kangaroo is the symbol of Australia. They have large eyes and ears. They don't walk, they jump.

They use their strong back legs. They can jump at 74 kilometers per hour. They can go over nine meters

in one jump. Kangaroo mothers have pouch to carry their babies. The babies stay inside to get milk and

keep warm.

     Kangaroos are everywhere in Australia. They are on TV, in books and in the shops. But do you

know that millions of kangaroos are killed every year? There are too many of them. There are about 20

to 25 million kangaroos in Australia. That's more than the number of people in the country. Some

kangaroos go hungry because there is not enough food to eat. They break into farms for food. Farms are

angry with them.

     The koalas is another famous Australian animals. They look like bears, have small eyes and big noses.

They eat leaves from gum trees. Koalas have a special smell. They use it to mark their home-"This is my

place, you can't come in. " Like kangaroos, a koalas baby lives in its mother's pouch, too.

1. If  we want to see kangaroos and koalas in natural forests, we can go to _              .

A. China            

B. France              

C. Australia

2. What does a kangaroo look like?

A. It looks like a bear.

B. It has big eyes and ears.

C. It has small eyes and big noses.

3. The word "pouch" means ________

A. 育儿袋            

B. 肌肉              

C. 尾巴

4. Which is not true?

A. The kangaroos can go over nine meters in one jump.

B. Koalas like eating leaves from gum trees.

C. Koalas use their voices to mark their homes.

5. What's the best title of this passage?

A.Kangaroos and koalas

B. Beautiful Australia

C. How to protect kangaroos and koalas

单项选择题