English for chemists

Scction II
Упр. 1. Прочтите заглавие текста 4 В. Бегло просмотрите его и кратко расскажите» о чем он.

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Упр. 2. а) Назовите значения следующих интернациональных слов:
essential, respiration, process, diatomic, litre, atmosphere, crystalline, laboratory, accelerate, distillation, control, condition, cylinder, electrolysis, condense
b) Назовите следующие элементы:
potassium, chlorine, manganese, nitrogen, hydrogen
Упр. 3. Определите значения выделенных слов по контексту.
1. Water is a compound with the formula H20 . 2. Oxygen supports combustion. 3. A gas which has no colour and odour is callcd colourless and odourless. 4. One litre of water at 0eC dissolves 48.9 ml of oxygen gas at Uatm pressure. 5. The boiling point of water is 100°C. 6. Waterfreezes at 0°C. 7. Above 0°C water is liquid and below 0°C it is solid. 8. Heating potassium chlorate is followed by the evolution of oxygen. 9. When water is boiling, it is evaporating. 10. Oxygen is stored in steel cylinders. 11. When the reaction proceeds very quickly, wc usually say that its rate is high. 12. In the laboratory oxygen is obtained by heating KClOj, and commercially it is made by the distillation of liquid air. 13. Oxygen is soluble in water very little.
Ошва к тексту:
fire — огонь; odour — запах; pale — бледный; melt — плавиться; amount— количество; volatile— летучий; tend— стремиться
Text 4 В
Прочтите текст про себя (контрольное время чтения — 5 минут).
Oxygen
Oxygen is one of the most abundant elements. It forms 21 per cent of the atmosphere, 89 per ccnt of the water, and about SO per ccnt of the earth’s crust. Without oxygen, life cannot exist, as well as fire. Oxygen is essential in supporting respiration and combustion, it is used in many modern industrial processes. The element consists of diatomic molecules.
It is a colourless, odourless gas, which is slightly soluble in water: 1 litre of water at 0° dissolves 48.9 ml of oxygen gas at I -atm pressure. Its density at 0°C and 1 atm is 1.429 g litre*1. Oxygen condenses to a pale blue liquid at its boiling point, -183.0°C, and on further cooling freezes at -218.4°C to a pale blue crystalline solid.
Oxygen is easily prepared in the laboratory by heating potassium chlorate,
KCIO,: 2KCIO, -> 2KC1 + 302 (g).

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The reaction proceeds at a temperature just above the melting point of potassium chlorate if a small amount of manganese dioxide, MnOj, is mixed with it. Although the manganese dioxide accelerates the rate of evolution of oxygen from the potassium chlorate, it itself is not changed.
Oxygen is made commercially mainly by the distillation of liquid air. Nitrogen is more volatile than oxygen, and tends to evaporate first from liquid air. Nearly pure oxygen is obtained by properly controlling the conditions of the evaporation. Oxygen is stored and shipped in steel cylinders, at pressures of 100 atm or more. Oxygen is also made commercially, together with hydrogen, by the electrolysis of water.
Упр. 4. Скажите, чем отличается текст 4 В от текста 4 А.
Упр. 5. Разделите текст на тематические части н озаглавьте каж-дую часть.
Упр. б. Скажите, что говорится в тексте:

1. 
   о распространении кислорода; 2) о его физических свойствах;
   

3. 
   о получении кислорода в лаборатории; 4) о промышленном полу­ чении кислорода; 5) о его хранении.
   

Упр. 7. Найдите в тексте и переведите на русский язык все предложе­ ния, в которых говорится о получении кислорода в промышленности.