learning english

1. 1. Pour a little vinegar into a plastic bottle with a
narrow neck.
2. put a little baking soda into a limp balloon. You can
use any shape and color of balloon. Hold it loosely by
the neck, with the open side of the balloon facing
towards you.
3. Stretch the neck of the balloon over the top of the
bottle.
4. lift the balloon up over the bottle and watch the
chemical reaction. The baking soda should fall out of
the balloon, through the neck of the bottle, and into the
vinegar at the bottom. Here, the two chemicals will fizz
and react, turning into other chemicals. One of these is
carbon dioxide, a gas, which will rise up and inflate
the balloon.

2. ANSWER THE QUESTION
1. What is the text about?
2. What do you need to do the
experiment?
3. What do you do before Stretch the neck
of the balloon?
4. What makes the balloon rise up and
inflate the balloon?
Hold it loosely by the neck,…
5. What does the underlined word refer to?