Most / Some / Plenty of people are already using hydrogen-powered cars.
The waste from these cars is pollution / water / fumes.
It’s expensive because it is new / uses hydrogen / is not common.
Hydrogen is more / less / just as dangerous as petrol.
Hydrogen will be used in gas / solid / liquid form.
Before you read
Discuss these questions with your partner.
What do you need to make a fire?
What happens to water at 10СГС?
-*■ How do we create ice, water and steam? How
can steam be turned back into water?
H D Vocabulary
Choose the correct answer a, в or с
from the list below.
With an air you can take air
out of a container.
Another word for a space, empty or not is a
A(n) is a substance that
increases the strength of hydronium if put in water.
A(n) is a substance that
increases the strength of hydroxide ions if put in water.
To make a(n) means you had
a try.
Somebody’s is the way they
do something.
1. When a light , it shines softly.
В The jar can hold a large
of liquid.
As the pressure increases, the danger of explosion increases in
10 Scientists carry out experiments and
|
... how matter changes its form. |
|
1 A pump |
В mixer |
С fan |
2 A jar |
В chamber |
С vacuum |
3 A alkali |
В acid |
С litmus |
4 A alkali |
В acid |
С litmus |
5 A start |
В go |
С attempt |
6 A attempt |
В approach |
С start |
7 A glows |
В dazzles |
С sparkles |
8 A volume |
В number |
С size |
9 A ratio |
В proportion С share |
|
10 A look |
В observe |
С see |
H Reading 2
Robert Boyle
My dear Hooke,
Your letter arrived yesterday. I think you are right to write a book of memories of your scientific work. I am delighted that you have asked me to remind you of your time as my assistant.
I asked you once to make an air pump for me. It was then a new idea and allowed me to create a vacuum by drawing out the air from a glass jar.
It was then that my experiments began. Perhaps this is something I will be remembered for, but I did not follow the scientific methods of the time. The traditional way to prove a fact was to argue it logically, and the conclusion must be the truth. Unfortunately, it was not always so. My approach was to observe what actually happened.
I placed a number of different objects into the vacuum chamber. One of them was a burning candle. The flame immediately went out. Another was a piece of coal, still glowing red from the fire. Once in the chamber it stopped glowing. If the air was put back in, and the coal was still hot, it would begin to glow again. From these observations I concluded that air was necessary for combustion to take place; nothing could bum without air. On another occasion, I placed my watch into the jar. I could hear it ticking as I drew the air out. Astonishingly, as the air was taken out of the chamber, the ticking became quieter. My conclusion: sound travels through air. If there is no air, sound cannot be heard.
As the air pump is actually taking something out of the jar, I thought, then that air must be made of something. My conclusion was that a gas is made up of very small particles. I reached this conclusion by observing the pressure in the vacuum jar. As the volume of gas is reduced, so the pressure increases in proportion. This is universally true and as you know, is now known as Boyle’s Law.
The work I did led me to the conclusion that chemistry is the science of the composition of substances. We chemists are here to try to understand how materials are made. In my opinion, an element is the one substance which cannot be broken down any further. We can discover what elements are in compounds.
When investigating these compounds, I discovered a way of testing them to find out if they are acid or alkali. I call it the litmus test.
I realise that there is much more for us to learn.
know that we can learn about the chemistry of the human body by observing how animals’ bodies behave in a vacuum. It is not work that I have attempted. It would mean I would have to kill the animals and dissect them afterwards to make my observations. I still cannot bring myself to kill an animal, let alone cut it up afterwards. This is work others will have to do.
Best wishes,
Boyle
Pronunciation guide
alkali Aaelkslai/ litmus /'litmas/ vacuum /'vaekjuam/
В E Comprehension
Read the text and decide if the following statements are true or false.
Boyle reached conclusions |
tD |
after observation. |
FD |
He found air needed to be present |
т □ |
to allow combustion. |
F □ |
The pressure in the jar |
T □ |
never changed. |
F □ |
He believed chemistry was all |
T □ |
about combustion. |
F □ |
He observed animals in a vacuum. |
T □ |
|
F □ |
Before you listen