Hydrogen is known to be the lightest of the elements. If the temperature is 20°C, it is an odourless, colourless, tasteless gas, its density being 0.08987, i.e. 1/15 that of air.
The gas is only slightly soluble in water, its solubility under standard pressure in 100 ml of water being 1,93 ml at 0°C.
Hydrogen could be found in the free state only in minute quantities because of its marked chemical activity.
Specialists consider hydrogen to be an extremely promising energy source. The reserves of hydrogen are known to be practically unlimited. Another plus is that hydrogen can be is as fuel in transport, industry and at home.
Extensive use of hydrogen as an energy source will help keep the environment clean.
Hydrogen is easy to transport and store. Even today, it costs several times less to transport by pipelines than to transmit electricity. Like any other gaseous fuel it could be accumulated and kept for a long time either in conventional or natural reservoirs.
Scientists have found many ways of producing hydrogen - basically from ordinary water, large volumes of this fuel could be obtained from coal, its reserves being tremendous.
FUEL
Carbon and hydrogen are the principal constituents of the solid fuels, coal and wood. Coal has been formed in nature by the slow decomposition of vegetable matter, in the presence of water and absence of air. Most of it was formed during the Carboniferous Period of geologic time, about 250 million years ago. Coal consists of free carbon mixed with various carbon compounds end some mineral matter. Anthracite coal (bard coal) contains much volatile matter, and burns with a smoky flame.
Bituminous coal can be converted into coke by heating without access of air. When the heating is carried out in a by-product coke oven, many substances distill out, including gas for fuel, ammonia, and a complex mixture of liquid and solid organic compounds. The solid material remaining in the ovens, consisting mainly of carbon, is called coke, it burns with a nearly colorless flame, and is used in great amounts in metallurgical processes.
Petroleum is a very important liquid fuel. It is a complex mixture of compounds of carbon and hydrogen.
The gas obtained from a coke furnace (coal gas) consists of hydrogen (about 30%), methane, carbon monoxide (10%) and minor components. This coal gas was the original illuminating gas.
Natural gas, from gas wells and oil wells, consists largely of methane.
Использованная литература:
1. Т.Ф. Березовская, А.И. Кожевникова. Учебное пособие по английскому языку/ Уфа, УНИ, 1993/ Часть 1. – 43 стр.
2. Т.Ф. Березовская, А.И. Кожевникова. Учебное пособие по английскому языку/ Уфа, УНИ, 1993/ Часть 2. – 183 стр.
3. Т.Ю. Дроздова, А.И. Берестова, В.Г. Маилова. English grammar./ Антология, Санкт-Петербург, 2004. – 399 стр.
4. Т.К. Цветкова. English grammar guide./ Проспект, Москва. 2008. – 163 стр.
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