《2026年名校金典课堂九年级英语上册人教版成都专版》

五、阅读短文，根据短文内容选择正确答案。
Blowing Up Balloons with CO₂
Chemical reactions（化学反应）make for some great experiments（实验）. You can make use of the CO₂ produced（产生）by a baking soda（小苏打）and lemon juice reaction to blow up your balloon!

What you'll need：
* Balloon
* About 40ml of water（a cup is about 250ml so you don’t need much）
* Soft drink bottle
* Juice from a lemon
* 1 spoon of baking soda
Instructions：
＞ Before you begin，make sure that you pull the balloon long to make it as easy as possible to blow up.
＞ Pour the 40ml of water into the soft drink bottle.
＞ Add the baking soda and mix it with water.
＞ Quickly put the balloon over the mouth of the bottle after you put the lemon juice in.
What's happening?
Adding the lemon juice to the baking soda creates a chemical reaction and produces CO₂. It rises up and escapes through the soft drink bottle. However，it doesn’t escape from the balloon. It pushes your balloon outwards and blows it up. Then，the balloon can inflate（膨胀）and you make it!
(C)1. What should you do before doing the experiment?
A. Drink some juice.
B. Blow up the balloon.
C. Pull the balloon long.
(B)2. In which sentence can you put the underlined word “escape” in?
A. She was lucky to the punishment.
B. Two criminals from the prison（监狱）.
C. The waste water and gas into the sea. It causes the pollution.
(B)3. The right order to finish the experiment is .
a. Pour 40ml of water into the soft drink bottle.
b. Add the baking soda to the bottle and mix it with water.
c. Pull the balloon long in order to make it easy to blow up.
d. Put the balloon over the mouth of the bottle.
e. Put the lemon juice into the bottle.
A. c-b-a-d-e
B. c-a-b-e-d
C. a-b-e-c-d
(C)4. What will be produced if you add lemon juice to the baking soda?
A. A soft drink.
B. Water.
C. CO₂.
(B)5. Where can we probably find the text?
A. Artistic Creations Weekly
B. Fun Science Kids
C. Everyday Cooking Guide

答案： C; B; B; C; B