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Look through the text again and find the sentences which are summarized in the following way:
The three forms of water are all the same chemical substances.
Water is the most abundant substance on the Earth.
Water can be decomposed into its elements by electrolysis.
Water’s chemical symbol is H20.
Water can be synthesized by burning hydrogen in air. 4 5
4. a) Read the text attentively using a dictionary and answer the following questions:
What makes water similar to other substances?
How is water in the form of gas called?
Can we call solid water ice?
What should we do to change one form of water into another? Give examples.
5. Why is water interesting from the chemical point of view?
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What important chemical reactions with water can you name?
How does water influence chemical reactions?
Why can’t water be an element?
What is the chemical name for water?
How can you get “artificial water”? What are its properties?
b) Read another text on water, put questions to some sentences so that to get the answers below; show the difference in oral and written presentation of the same problem:
Water is a compound of hydrogen and oxygen.
Water vapour.
Because of its physical properties.
Water is purified by distillation.
It’s 0° C.
Greasy, fatty substances or most plastics.
It’s colourless, tasteless, and odourless.
It’s 100° C.
Water is hydrogen oxide, a compound of hydrogen and oxygen. It can be made if hydrogen or a hydrogen-containing substance is burnt in air or oxygen.
Most of the world’s water is liquid, but an important fraction is solid as ice and snow.
Many mineral substances contain water of crystallization (e. g., copper sulphate) and in the atmosphere there are millions of tons of water vapour. Clouds consist of minute droplets of water or crystals of ice.
Water dissolves a very large number of substances and is the most important solvent. It does not dissolve greasy, fatty substances or most plastics.
After they had found the composition of water, the scientists could investigate its properties. It was stated that ordinary water is impure, it usually contains dissolved salts and dissolved gases, and sometimes organic matter.
For chemical work water is to be purified by distillation. Pure water is colourless, tasteless, and odourless. Rain water formed by condensation of water in the air is nearly pure water, which contains only small proportions of the dust and of dissolved gases.
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a) to warm up
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Ю
|
water
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b) usually
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i)
|
viewpoint
|
c) stream
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m)
|
synthetic
|
d) steam
|
n)
|
to fire
|
e) to chill
|
o)
|
rigorous
|
0 hazardous
|
P)
|
to hide
|
g) the 4th part of a whole
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q)
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significance
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h) noted
|
r)
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the outer part
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i) state
|
s)
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precisely
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j) thus
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A
|
|
В
|
1. the commonest
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a)
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impossible
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2. like
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b)
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the most unusual
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3. simple
|
c)
|
old
|
4. usually
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d)
|
common
|
5. new
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e)
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few
|
6. single
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0
|
exceptionally
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7. many
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g)
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to lose
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8. decomposition
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h)
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natural
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9. to obtain
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0
|
unlike
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10. possible
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j)
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integration
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11. easy
|
k)
|
complicated
|
12. dangerous
|
1)
|
secure
|
13. artificial
|
m)
|
lenient
|
14. strict
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n)
|
difficult
|
Study carefully grammar table 7 in Appendix 1 and change the given sentences into indirect speech:
The author writes: “Three-quarters of the Earth is covered in water.”
The writer asks: “Is it possible to make water from its elements?”
The scientists stated: “The radiation from thorium nitrate is unsteady.”
Rutherford remarked: “It’s really very fine to see the things one has seen in imagination visibly demonstrated.”
He said: “I have already drawn your attention to the social implications of the release of atomic energy.”
Pauling often repeated: “I keep on the outlook for aspects that I don’t understand.”
The scholars usually asked: “What causes electrons to change orbits?”
They also asked: “Is the electron a wave or a particle?”
Listen to the following dialogue and choose the title out of the given ones.
The notes and words will help you to understand the conversation better.
Water in Our Life.
The Composition of Water.
The Water Cycle.
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NOTES
you see — видишь ли
getting down on paper — записываю
kind of — что-то вроде
Why? — А что?
You know what? — Знаешь что?
Wiit a tick — Подожди минутку.
Right you are. — зд. Ну вот (я готов).
Fire away — Начинай.
to get the figures — записать цифры
Mind you. — Слушай внимательно.
I’ve got that. — Я понял.
Go on, will you? — Продолжай же!
You know — знаешь ли
I didn’t — я не (говорила)
I mean — я хочу сказать
That’s incredible. — Невероятно.
Did you get it all down? — Ты все записал?
My pleasure! — Всегда готов помочь!
I can’t wait — не могу дождаться
Have a good day. — Всего хорошего.
WORDS
to check — проверить
circulation — циркуляция
deadline — последний срок
to deposit — отлагать(ся)
dew — роса
figures — цифры
fresh — свежий
hail — град
hurricane - ураган
lake — озеро
total — общий
plant — растение press — печать quantity — количество recently — недавно relatively - относительно to release -- освобождать(ся) soil — почва
to sublime — сублимировать thunderstorm — гроза tornado — торнадо (ветер)
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SUSAN:
NICK:
SUSAN:
NICK:
SUSAN:
NICK:
SUSAN:
NICK:
SUSAN:
4NICK: SUSAN:
NICK:
SUSAN:
NICK:
SUSAN:
NICK:
SUSAN:
NICK:
SUSAN:
NICK:
SUSAN:
NICK:
SUSAN:
Look, Nick... about the article you’ve got to write...
On water? Well, I’m working on it right now. Getting down on paper the most essential facts... kind of... common knowledge. Why?
Good. You know what? There’s something that might be of interest. It’s from a book published recently. I’ve made a copy but I can’t find it.
Pity. Wait a minute... while I get a paper.and a pen. Perhaps you’d tell me about it. Later 1 could check the details.
O.K.
(Pause.)
Right you are. Fire away.
Well, try to get the figures. They’re important..
Yes, I will.
Mind you, it’s about water circulation. As you know, Earth’s water passes through a great cycle. But how it happens? First, it evaporates from oceans, lakes, rivers, soil and plants...
Wait a tick. Did you say soil and plants?
That’s right... and sublimes from snow and ice into the atmosphere.
Where did you say it sublimes into?
I said it sublimes into the atmosphere.
Right.
Second. The sun supplies the energy needed for evaporation and sublimation. Winds move the water vapour around.
I’ve got that... go on, will you.
Well... water then returns to the Earth as snow or rain...
Only in two forms?
You see, you may also write as hail and dew if you like. Third. When water vapour condences to liquid water or deposits as solid ice, energy is released.
Yes, what happens then?
In fact, the transfer of energy by evaporation and condensation of water are major facts of the weather.
What about energy release by thunderstorms, tornadoes, and hurricanes? Does it happen?
I think it’s obvious. However the quantity of water vapour in the atmosphere at any time is relatively small.
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NIC К: How small did you say it is?
SUSAN: I didn’t. Pm just going to tell you about this, — only about
001 percent of the total water on the Earth. However, the quantity of water that passes through the atmosphere in a year is large. I mean much greater than the total volume of fresh water on the Earth. That’s it.
NICK: That’s incredible, Susan.
SUSAN: Did you get it all down?
NICK: Yeah... I think so... thank you, Susan.
SUSAN: My pleasure. I hope you’ll get that article finished soon. When’s it to go to press?
NICK: End of the week... is the deadline. One of the copies is yours.
SUSAN: O.K. I can’t wait to see it published.
NICK: Thanks again.
SUSAN: Have a good day.
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