Put the words from the box into the text.
| impractical, volume, operate, troublesome, application, purposes, considerable, proved, diseases, variety, install |
Although by far the greatest (1) of oxygen is used for industrial (2), an ever increasing amount of oxygen is being used in the treatment of certain (3). The (4) of diseases and ailments in which oxygen treatments have (5) beneficial is wide, ranging from pneumonia and heart disease to far less serious but yet (6) conditions in which oxygen may be lacking. The relief of oxygen-want at high altitudes is an (7) that has received (8) notice recently through the decision of many commercial airlines to (9) oxygen-administration equipment in their airplanes. While breathing oxygen, aircraft pilots can (10) efficiently at altitudes that would be (11) without it.
Complete the sentences using the appropriate derivatives of the words on the right.
| The (1) industry uses vast amounts of oxygen every year in a (2) of chemical synthesis reactions. One of the most important of these is the (3) of hydrocarbons by oxygen. Under most circumstances, heating a hydrocarbon with oxygen results in (4), with carbon dioxide and water as the main (5). However, if the rate at which oxygen is fed into a hydrocarbon mixture is (6) controlled, the hydrocarbon is "cracked," or (7) apart to produce other products, such as acetylene, ethylene, and propylene. Perhaps the best known (8) (9) of oxygen is in oxygen therapy, where patients who have trouble breathing take doses of (10) or nearly (11) oxygen. Some common instances in which oxygen (12) is used include surgical procedures, following heart attacks, and during (13) diseases. | chemistry |
| various | |
| crack | |
| combustible | |
| produce | |
| care | |
| break | |
| medicine | |
| apply | |
| impurity | |
| purify | |
| therapeutic | |
| infection |
Translate the sentences into English. Mind Passive Voice .
1. Кислород уже давно применяется в промышленности. 2. Кислород обычно получают из воздуха путём его сжижения и фракционной перегонки. 3. В техническом отношении этот процесс сложен. 4. Жидкий воздух – это очень холодная смесь жидкого кислорода и жидкого азота. 5. Когда карбид кальция обрабатывают водой, получается ацетилен. 6. В настоящее время кислородно-ацетиленовая сварка и резка металлов применяется почти во всех отраслях промышленности. 7. Огромное количество кислорода используют ежегодно для промышленных целей. 8. Развитие некоторых отраслей промышленности ускорилось благодаря сварке. 9. Наиболее известным применением кислорода в медицинских целях является кислородная терапия, при которой пациенты с затруднённым дыханием принимают чистый или почти чистый кислород. 10. Решение авиакомпаний использовать подающее кислород оборудование в самолётах решило проблему нехватки кислорода на большой высоте.
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Answer the following questions.
1. Who gave name to oxygen? When did it happen?
2. How long has oxygen been used in industry?
3. What can you say about the industrial application of oxygen in the nineteenth century?
4. What industrial application of oxygen is known best of all?
5. What fields of industry rely on the oxy-acetylene process?
6. In what ways does chemical industry apply oxygen?
7. How has oxygen helped aircraft pilots operate at high altitudes?
8. Is it possible to name oxygen our best friend? Why?
Section II
TEXT B
Notes on the text:
silent discharge – тихий разряд; pass through a vessel – проходить через сосуд; bond – связь; undergo – подвергаться; whereas – в то время как; toxic exposure – отравление; detectable – обнаружимый; account for –отвечать за
Skim the text and entitle it.
Common methods for ozone generation are ultraviolet radiation, silent electric arc and electrolysis. The ultraviolet radiation technique is used only when relatively low concentrations are required, e.g. for environmental study. The electrolysis of water is not widely used because of low efficiency. So far, the action of silent electric discharge on oxygen is the most common method for the production of ozone, it gives a yield of 6% by weight of ozone.
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When high purity or quantity of ozone is desirable, it is possible to use liquid ozone. The ozone-oxygen mixture from one of the above methods is passed through a vessel at liquid oxygen temperature (–183ºC). Because of the large difference in the vapour pressure of ozone and oxygen, oxygen is pumped off from the mixture whereas ozone is liquefied. Liquid ozone is then vaporized from the concentrated system for further use.
Ozone is a colourless gas with characteristic odour which is detectable by nose and provides a warning of toxic exposure. The ozone molecule is non-linear with a bond angle of 116º. In contrast to oxygen, gaseous ozone is diamagnetic and possesses four resonance structures accounting for its electrophilic nature.
Mechanistic studies of the biological effect of ozone are of particular interest. Vitamin E prolongs the life of rats exposed to ozone. This is based on the observation that the vitamin E-depleted group undergoes a more significant change than the vitamin E-supplemented group in the fatty acid composition of total lung lipid. Therefore vitamin E, the biological antioxidant, provides protection from ozone toxicity. Ozone is particularly destructive substance to rubber and other elastomers.
In nature oxygen forms ozone during lightning discharges, and at altitudes of 10,000 – 30,000 metres through the action of solar ultraviolet radiation. Ozone removes harmful ultraviolet radiation from sunlight and also absorbs the Earth's own infra-red radiation thus protecting it against cooling. Therefore the ozone belt plays a major role in protecting life on Earth.
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